PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
Active Asset Allocation Portfolio – Real Return Oriented
PIMCO All Asset Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO All Asset Portfolio

Investment Objective
The Portfolio seeks maximum real return, consistent with preservation of real capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.425%
Distribution and/or Service (12b-1) Fees
0.15%
Acquired Fund Fees and Expenses(1)
0.80%
Total Annual Portfolio Operating Expenses(2)
1.375%
Fee Waiver and/or Expense Reimbursement(3)
(0.10%)
Total Annual Portfolio Operating Expenses After Fee Waiver
and/or Expense Reimbursement
1.275%
1
Acquired Fund Fees and Expenses include interest expense of the Underlying PIMCO Funds of 0.06%. Interest expense can result from certain transactions within the Underlying PIMCO Funds and is separate from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense of the Underlying PIMCO Funds, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 1.215% for Administrative Class shares.
2
Total Annual Portfolio Operating Expenses do not match the Ratio of Expenses to Average Net Assets Excluding Waivers of the Portfolio, as set forth in the Financial Highlights table of the Portfolio’s prospectus, because the Ratio of Expenses to Average Net Assets Excluding Waivers reflects the operating expenses of the Portfolio and does not include Acquired Fund Fees and Expenses.
3
PIMCO has contractually agreed, through May 1, 2022, to reduce its advisory fee to the extent that the Underlying PIMCO Fund Expenses attributable to advisory and supervisory and administrative fees exceed 0.64% of the total assets invested in Underlying PIMCO Funds. PIMCO may recoup these waivers in future periods, not exceeding three years from the date of waiver, provided total expenses, including such recoupment, do not exceed the annual expense limit that was in place at the time the amount being recouped was originally waived and the current annual expense limit. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. The fee reduction is implemented based on a calculation of Underlying PIMCO Fund Expenses attributable to advisory and supervisory and administrative fees that is different from the calculation of Acquired Fund Fees and Expenses listed in the table above.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or
lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$130
$426
$743
$1,643
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 141% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio is a “fund of funds,” which is a term used to describe mutual funds that pursue their investment objective by investing in other funds. The Portfolio seeks to achieve its investment objective by investing under normal circumstances substantially all of its assets in the least expensive class of shares of any actively managed or smart beta funds (including mutual funds or exchange-traded funds) of PIMCO Funds, PIMCO ETF Trust or PIMCO Equity Series, each an affiliated open-end investment company, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management (collectively, “Underlying PIMCO Funds”). As used in the investment objective, “real return” equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure, and “real capital” equals capital less the estimated cost of inflation measured by the change in an official inflation measure. In addition to investing in Underlying PIMCO Funds, at the discretion of PIMCO and without shareholder approval, the Portfolio may invest in additional Underlying PIMCO Funds created in the future.
The Portfolio invests its assets in shares of the Underlying PIMCO Funds and does not invest directly in stocks or bonds of other issuers. Research Affiliates, the Portfolio’s asset allocation sub-adviser, determines how the Portfolio allocates and reallocates its assets among the Underlying PIMCO Funds. In doing so, the asset allocation sub-adviser seeks concurrent exposure to a broad spectrum of asset classes.
Investments in Underlying PIMCO Funds.The Portfolio may invest in any or all of the Underlying PIMCO Funds, but will not normally invest in every Underlying PIMCO Fund at any particular time. The Portfolio’s investment in a particular Underlying PIMCO Fund normally will not exceed 50% of its total assets. The Portfolio will not invest in the Short Strategy Underlying PIMCO Funds, which seek to gain a negative exposure to an asset class such as equities. The Portfolio’s combined investments in the Equity-Related Underlying PIMCO Funds will not exceed 50% of its total assets. In addition, the Portfolio’s combined investments in Inflation-Related Underlying PIMCO Funds, which seek to gain exposure to an asset class such as U.S. Treasury

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Inflation-Protected Securities (“TIPS”), commodities, or real estate, normally will not exceed 75% of its total assets.
Asset Allocation Investment Process.The Portfolio’s assets are not allocated according to a predetermined blend of shares of the Underlying PIMCO Funds. Instead, when making allocation decisions among the Underlying PIMCO Funds, the Portfolio’s asset allocation sub-adviser considers various quantitative and qualitative data relating to the U.S. and foreign economies and securities markets. Such data includes projected growth trends in the U.S. and foreign economies, forecasts for interest rates and the relationship between short- and long-term interest rates (yield curve), current and projected trends in inflation, relative valuation levels in the equity and fixed income markets and various segments within those markets, the outlook and projected growth of various industrial sectors, information relating to business cycles, borrowing needs and the cost of capital, political trends, data relating to trade balances and labor information. The Portfolio’s asset allocation sub-adviser has the flexibility to reallocate the Portfolio’s assets among any or all of the asset class exposures represented by the Underlying PIMCO Funds based on its ongoing analyses of the equity, fixed income and commodity markets. While these analyses are performed daily, material shifts in asset class exposures typically take place over longer periods of time.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Principal Risks of the Portfolio
Allocation Risk:the risk that a Portfolio could lose money as a result of less than optimal or poor asset allocation decisions. The Portfolio could miss attractive investment opportunities by underweighting markets that subsequently experience significant returns and could lose value by overweighting markets that subsequently experience significant declines
Fund of Funds Risk:the risk that a Portfolio’s performance is closely related to the risks associated with the securities and other investments held by the Underlying PIMCO Funds and that the ability of a Portfolio to achieve its investment objective will depend upon the ability of the Underlying PIMCO Funds to achieve their investment objectives
Certain principal risks of investing in the Underlying PIMCO Funds, and consequently the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Certain Principal Risks of Underlying PIMCO Funds
Market Trading Risk:the risk that an active secondary trading market for shares of an Underlying PIMCO Fund that is an exchange-traded fund does not continue once developed, that such Underlying PIMCO Fund may not continue to meet a listing exchange’s trading or listing requirements, or that such Underlying PIMCO Fund’s shares trade at prices other than the Fund’s net asset value
Municipal Project-Specific Risk:the risk that an Underlying PIMCO Fund may be more sensitive to adverse economic, business or political developments if it invests a substantial portion of its assets in the bonds of specific projects (such as those relating to education, health care, housing, transportation, and utilities), industrial development bonds, or in bonds from issuers in a single state
Municipal Bond Risk:the risk that an Underlying PIMCO Fund may be affected significantly by the economic, regulatory or political developments affecting the ability of issuers of debt securities whose interest is, in the opinion of bond counsel for the issuer at the time of issuance, exempt from federal income tax (“Municipal Bonds”) to pay interest or repay principal
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Distressed Company Risk:the risk that securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services

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PIMCO All Asset Portfolio

Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. An Underlying PIMCO Fund’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Underlying PIMCO Fund’s ability to invest in derivatives, limit the Underlying PIMCO Fund’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Underlying PIMCO Fund’s performance
Futures Contract Risk:the risk that, while the value of a futures contract tends to correlate with the value of the underlying asset that it represents, differences between the futures market and the market for the underlying asset may result in an imperfect correlation. Futures contracts may involve risks different from, and possibly greater than, the risks associated with investing directly in the underlying assets. The purchase or sale of a futures contract may result in losses in excess of the amount invested in the futures contract
Model Risk:the risk that an Underlying PIMCO Fund’s investment models used in making investment allocation decisions, and the indexation methodologies used in constructing an underlying index for an Underlying PIMCO Fund that seeks to track the investment results of such underlying index, may not adequately take into account certain factors and may result in a decline in the value of an investment in the Underlying PIMCO Fund
Commodity Risk:the risk that investing in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or
factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Real Estate Risk:the risk that the Portfolio’s investments in Real Estate Investment Trusts (“REITs”) or real estate-linked derivative instruments will subject the Portfolio to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. A Portfolio’s investments in REITs or real estate-linked derivative instruments subject it to management and tax risks. In addition, privately traded REITs subject a Portfolio to liquidity and valuation risk
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Smaller Company Risk:the risk that the value of securities issued by a smaller company may go up or down, sometimes rapidly and unpredictably as compared to more widely held securities, due to narrow markets and limited resources of smaller companies. A Portfolio’s investments in smaller companies subject it to greater levels of credit, market and issuer risk
Issuer Non-Diversification Risk:the risk of focusing investments in a small number of issuers, including being more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Portfolios that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified”
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO, or Research Affiliates, and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO or Research Affiliates to restrict or prohibit participation in certain investments.. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Tax Risk:the risk that the tax treatment of swap agreements and other derivative instruments, such as commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures, may be affected by future regulatory or legislative changes that could affect whether income from such investments is “qualifying income” under Subchapter M of the Internal Revenue Code, or otherwise affect the character, timing and/or amount of the Portfolio’s taxable income or gains and distributions
Subsidiary Risk:the risk that, by investing in certain Underlying PIMCO Funds that invest in a subsidiary (each a “Subsidiary”), the Portfolio is indirectly exposed to the risks associated with a Subsidiary’s investments. The Subsidiaries are not registered under the 1940 Act and may not be subject to all the investor protections of the 1940 Act. There is no guarantee that the investment objective of a Subsidiary will be achieved
Value Investing Risk:a value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
Exchange-Traded Fund Risk:the risk that an exchange-traded fund may not track the performance of the index it is designed to track, among other reasons, because of exchange rules, market prices of shares of an exchange-traded fund may fluctuate rapidly and materially, or shares of an exchange-traded fund may trade significantly above or below net asset value, any of which may cause losses to the Portfolio invested in the exchange-traded fund
Tracking Error Risk:the risk that the portfolio of an Underlying PIMCO Fund that seeks to track the investment results of an underlying index may not closely track the underlying index for a number of reasons. The Underlying PIMCO Fund incurs operating expenses, which are not applicable to the underlying index, and the costs of buying and selling securities, especially when rebalancing the Underlying PIMCO Fund’s portfolio to reflect changes in the composition of the underlying index. Performance of the Underlying PIMCO Fund and the underlying index may vary due to asset valuation differences and differences between the Underlying PIMCO Fund’s portfolio and the underlying index due to legal restrictions, cost or liquidity restraints. The risk that performance of the Underlying PIMCO Fund and the underlying index may vary may be heightened during periods of increased market volatility or other unusual market conditions. In addition, an Underlying PIMCO Fund’s use of a representative sampling approach may cause the Underlying PIMCO Fund to be less correlated to the return of the underlying index than if the Underlying PIMCO Fund held all of the securities in the underlying index
Indexing Risk:the risk that an Underlying PIMCO Fund that seeks to track the investment results of an underlying index is negatively affected by general declines in the asset classes represented by the underlying index
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by an Underlying PIMCO Fund rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Underlying PIMCO Fund or on certain instruments in which the Underlying PIMCO Fund invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in value of certain instruments held by the Underlying PIMCO Fund
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

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PIMCO All Asset Portfolio

Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index and an index of similar funds. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio measures its performance against a primary benchmark and a secondary benchmark. The Bloomberg Barclays U.S. TIPS: 1-10 Year Index, the primary benchmark, is an unmanaged index comprised of U.S. Treasury Inflation-Protected securities having a maturity of at least 1 year and less than 10 years. The CPI + 500 Basis Points benchmark, the secondary benchmark, is created by adding 5% to the annual percentage change in the Consumer Price Index (“CPI”). The CPI is an unmanaged index representing the rate of inflation of the U.S. consumer prices as determined by the U.S. Bureau of Labor Statistics.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
June 30, 2020
12.08%
Worst Quarter
March 31, 2020
-16.11%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Administrative Class Return
8.01%
7.95%
4.65%
Bloomberg Barclays U.S. TIPS: 1-10 Year Index (reflects
no deductions for fees, expenses or taxes)
8.39%
4.13%
2.88%
Consumer Price Index + 500 Basis Points (reflects no
deductions for fees, expenses or taxes)
6.29%
6.94%
6.73%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. Research Affiliates serves as the asset allocation sub-adviser to the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Robert D. Arnott and Christopher J. Brightman. Mr. Arnott is the Chairman and Founder of Research Affiliates and he has managed the Portfolio since its inception in April 2003. Mr. Brightman is Chief Investment Officer of Research Affiliates and he has managed the Portfolio since November 2016.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

5  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments in the Underlying PIMCO Funds. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Underlying PIMCO Funds, and consequently the Portfolio, are identified in the Portfolio Summary and are described in this section. The Portfolio and the Underlying PIMCO Funds may be subject to additional risks other than those identified and described below because the types of investments made by an Underlying PIMCO Fund can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Underlying PIMCO Funds, their investments and the related risks. There is no guarantee that the Portfolio or the Underlying PIMCO Funds will be able to achieve their investment objectives. It is possible to lose money by investing in the Portfolio.
Allocation Risk
The Portfolio’s investment performance depends upon how its assets are allocated and reallocated between the Underlying PIMCO Funds according to the Portfolio’s asset allocation targets and ranges. A principal risk of investing in the Portfolio is that the asset allocation sub-adviser will make less than optimal or poor asset allocation decisions. The asset allocation sub-adviser attempts to identify investment allocations for the Underlying PIMCO Funds that will provide consistent, quality performance for the Portfolio, but there is no guarantee that such allocation techniques will produce the desired results. It is possible that the asset allocation sub-adviser will focus on an Underlying PIMCO Fund that performs poorly or underperforms other Underlying PIMCO Funds under various market conditions. You could lose money on your investment in the Portfolio as a result of these allocation decisions.
Fund of Funds Risk
Because the Portfolio invests substantially all of its assets in Underlying PIMCO Funds, the risks associated with investing in the Portfolio are closely related to the risks associated with the securities and other investments held by the Underlying PIMCO Funds. The ability of the Portfolio to achieve its investment objective will depend upon the ability of the Underlying PIMCO Funds to achieve their respective investment objectives. There can be no assurance that the investment objective of any Underlying PIMCO Fund will be achieved.
The Portfolio’s net asset value (“NAV”) will fluctuate in response to changes in the respective NAVs of the Underlying PIMCO Funds in which it invests. The extent to which the investment performance and risks associated with the Portfolio correlate to those of a particular Underlying PIMCO Fund will depend upon the extent to which the Portfolio’s assets are allocated from time to time for investment in the Underlying PIMCO Fund, which will vary. To the extent that the Portfolio invests a significant portion of its assets in an Underlying PIMCO Fund, it will be particularly sensitive to the risks associated with that Underlying PIMCO Fund.
Market Trading Risk
An Underlying PIMCO Fund that is an exchange-traded fund is subject to secondary market trading risks. Once operational, shares of the Underlying PIMCO Fund are listed for trading on an exchange, however, there can be no guarantee that an active trading market for such shares will develop or continue. Shares of the Underlying PIMCO Fund may be listed or traded on U.S. and foreign (non-U.S.) exchanges other than the Underlying PIMCO Fund’s primary U.S. listing exchange. There can be no guarantee that the Underlying PIMCO Fund’s shares will continue trading on any exchange or in any market or that the Underlying PIMCO Fund’s shares will continue to meet the listing or trading requirements of any exchange or market. The Underlying PIMCO Fund’s shares may experience higher trading volumes on one exchange as compared to another and investors are subject to the execution and settlement risks of the market where their broker directs trades.
Secondary market trading in the Underlying PIMCO Fund’s shares may be halted by an exchange because of market conditions. Pursuant to exchange or market rules, trading in the Underlying PIMCO Fund’s shares on an exchange or in any market may be subject to trading halts caused by extraordinary market volatility. If secondary market trading is halted or an exchange closes earlier than anticipated, you may be unable to purchase or sell Portfolio shares. There can be no guarantee that the Underlying PIMCO Fund’s exchange listing or ability to trade its shares will continue or remain unchanged. In the event the Underlying PIMCO Fund ceases to be listed on an exchange, the Underlying PIMCO Fund may cease operating as an “exchange-traded” fund and operate as a mutual fund, provided that shareholders are given advance notice.
Buying or selling the Underlying PIMCO Fund’s shares on an exchange may require the payment of brokerage commissions. In addition, an investor who buys or sells the Underlying PIMCO Fund’s shares may also incur the cost of the spread (the difference between the bid price and the ask price). The commission is frequently a fixed amount and may be a significant cost for investors seeking to buy or sell small amounts of shares. The spread varies over time for shares of the Underlying PIMCO Fund based on their trading volume and market liquidity, and is generally less if the Underlying PIMCO Fund has more trading volume and market liquidity and more if the Underlying PIMCO Fund has less trading volume and market liquidity. Due to the costs inherent in buying or selling the Underlying PIMCO Fund’s shares, frequent trading may detract significantly from investment returns. Investment in the Underlying PIMCO Fund’s shares may not be advisable for investors who expect to engage in frequent trading.

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Shares of the Underlying PIMCO Fund may trade on an exchange at prices at, above or below their most recent NAV. The market prices of an Underlying PIMCO Fund’s shares will fluctuate, sometimes rapidly and materially, in response to changes in the Underlying PIMCO Fund’s NAV, the value of the Underlying PIMCO Fund’s holdings and supply and demand for the Underlying PIMCO Fund’s shares. Although the creation/redemption feature of the Underlying PIMCO Funds generally makes it more likely that an Underlying PIMCO Fund’s shares will trade close to NAV, market volatility, lack of an active trading market for the Underlying PIMCO Fund’s shares, disruptions at market participants (such as authorized participants or market makers) and any disruptions in the ordinary functioning of the creation/redemption process may result in the Underlying PIMCO Fund’s shares trading significantly above (at a “premium”) or below (at a “discount”) NAV. An investor who buys or sells an Underlying PIMCO Fund’s shares may incur significant losses if the investor transacts in the Underlying PIMCO Fund’s shares in these and other circumstances. Neither PIMCO nor the Trust can predict whether an Underlying PIMCO Fund’s shares will trade above, below or at NAV. An Underlying PIMCO Fund’s investment results are based on the Underlying PIMCO Fund’s daily NAV. Investors transacting in an Underlying PIMCO Fund’s shares in the secondary market, where market prices may differ from NAV, may experience investment results that differ from results based on the Underlying PIMCO Fund’s daily NAV.
Municipal Project-Specific Risk
An Underlying PIMCO Fund may be more sensitive to adverse economic, business or political developments if it invests a substantial portion of its assets in the bonds of specific projects (such as those relating to education, health care, housing, transportation, and utilities), industrial development bonds, or in general obligation bonds, particularly if there is a large concentration from issuers in a single state.
Municipal Bond Risk
An Underlying PIMCO Fund that invests in Municipal Bonds may be affected significantly by the economic, regulatory or political developments affecting the ability of issuers of Municipal Bonds to pay interest or repay principal. In addition, the ability of an issuer to make payments or repay interest may be affected by litigation or bankruptcy. In the event of bankruptcy of such an issuer, an Underlying PIMCO Fund investing in the issuer’s securities could experience delays in collecting principal and interest, and the Underlying PIMCO Fund may not, in all circumstances, be able to collect all principal and interest to which it is entitled. To enforce its rights in the event of a default in the payment of interest or repayment of principal, or both, an Underlying PIMCO Fund may, in some instances, take possession of, and manage, the assets securing the issuer’s obligations on such securities, which may increase the Underlying PIMCO Fund’s operating expenses. Any income derived from the Underlying PIMCO Fund’s ownership or operation of such assets may not be tax-exempt. Municipal Bonds are subject to interest rate, credit and market risk.
Because many Municipal Bonds are issued to finance similar projects (such as those relating to education, health care, housing, transportation, and utilities), conditions in those sectors may affect the overall municipal securities market. In addition, changes in the financial condition of an individual municipal issuer can affect the overall municipal market. Municipal Bonds backed by current or anticipated revenues from a specific project or specific assets can be negatively affected by the discontinuance of the supporting taxation or the inability to collect revenues for the specific project or specific assets. Municipal Bonds are subject to the risk that the Internal Revenue Service (“IRS”) may determine that an issuer has not complied with applicable tax requirements and that interest from the Municipal Bond is taxable, which may result in a significant decline in the value of the security. Municipal Bonds may be less liquid than taxable bonds and there may be less publicly available information on the financial condition of Municipal Bond issuers than for issuers of other securities, and the investment performance of an Underlying PIMCO Fund investing in Municipal Bonds may therefore be more dependent on the analytical abilities of PIMCO than if the Underlying PIMCO Fund held other types of investments such as stocks or taxable bonds. The secondary market for Municipal Bonds also tends to be less well-developed or liquid than many other securities markets, a by-product of lower capital commitments to the asset class by the dealer community, which may adversely affect an Underlying PIMCO Fund’s ability to sell Municipal Bonds it holds at attractive prices or value Municipal Bonds.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in an Underlying PIMCO Fund’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Underlying PIMCO Fund is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and an Underlying PIMCO Fund may lose money as a result of movements in interest rates. An Underlying PIMCO Fund may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.

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Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When an Underlying PIMCO Fund holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Underlying PIMCO Fund’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Underlying PIMCO Fund may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Underlying PIMCO Fund is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Underlying PIMCO Fund. This is especially the case if the Underlying PIMCO Fund consists of securities with widely varying durations. Therefore, if the Underlying PIMCO Fund has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Underlying PIMCO Fund uses leverage or derivatives in connection with the management of the Underlying PIMCO Fund.
Convexity is an additional measure used to understand a security’s or an Underlying PIMCO Fund‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Underlying PIMCO Fund holds such securities, the Underlying PIMCO Fund may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
An Underlying PIMCO Fund could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/ or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by an Underlying PIMCO Fund may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Underlying PIMCO Fund. This is especially the case if the Underlying PIMCO Fund consists of securities with widely varying credit ratings. Therefore, if the Underlying PIMCO Fund has an average credit rating that suggests a certain credit quality, the Underlying PIMCO Fund may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Underlying PIMCO Fund uses leverage or derivatives in connection with the management of the Underlying PIMCO Fund. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/ or interest.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

High Yield Risk
Underlying PIMCO Funds that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Distressed Company Risk
An Underlying PIMCO Fund that invests in securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments. Issuers of distressed company securities may also be involved in restructurings or bankruptcy proceedings that may not be successful. An economic downturn or period of rising interest rates could adversely affect the market for these securities and reduce the Underlying PIMCO Fund’s ability to sell these securities (liquidity risk). If the issuer of a debt security is in default with respect to interest or principal payments, the Underlying PIMCO Fund may lose its entire investment.
Market Risk
The market price of securities owned by an Underlying PIMCO Fund may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors which affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by an Underlying PIMCO Fund. Even when markets perform well, there is no assurance that the investments held by an Underlying PIMCO Fund will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Underlying PIMCO Funds to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Underlying PIMCO Funds’ investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi- governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the

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ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent an Underlying PIMCO Fund from executing advantageous investment decisions in a timely manner. Underlying PIMCO Funds that have focused their investments in a region enduring geopolitical market disruption will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to an Underlying PIMCO Fund’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Underlying PIMCO Fund to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause an Underlying PIMCO Fund to lose enough value, the Underlying PIMCO Fund could also face increased shareholder redemptions, which could force the Underlying PIMCO Fund to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Underlying PIMCO Fund.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, an Underlying PIMCO Fund being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAVs, delays in NAV calculation and/or the inability to calculate NAVs over extended periods.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Underlying PIMCO Funds reasonably expect cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. An Underlying PIMCO Fund’s investments in illiquid investments may reduce the returns of the Underlying PIMCO Fund because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Underlying PIMCO Fund to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Underlying PIMCO Fund from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, an Underlying PIMCO Fund, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that an Underlying PIMCO Fund principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Underlying PIMCO Fund will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for an Underlying PIMCO Fund to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require an Underlying PIMCO Fund to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Underlying PIMCO Fund, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Underlying PIMCO Funds may use are referenced under “Characteristics and Risks of Securities and Investment Techniques-Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. Underlying PIMCO Funds may also use derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. Underlying PIMCO Funds may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject an Underlying PIMCO Fund to the potential for unlimited loss. The use of derivatives may cause the Underlying PIMCO Fund’s investment returns to be impacted by the performance of securities the Underlying PIMCO Fund does not own and result in the Underlying PIMCO Fund’s total investment exposure exceeding the value of its portfolio.
An Underlying PIMCO Fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of the derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Underlying PIMCO Fund may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Underlying PIMCO Fund are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Underlying PIMCO Fund, or the derivatives or other strategies used by the Underlying PIMCO Fund, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Underlying PIMCO Fund invests. By investing in a derivative instrument, the Underlying PIMCO Fund could lose more than the initial amount invested, and derivatives may increase the volatility of the Underlying PIMCO Fund, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that an Underlying PIMCO Fund will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, an Underlying PIMCO Fund’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders.
Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Underlying PIMCO Fund’s clearing broker, or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which an Underlying PIMCO Fund may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If an Underlying PIMCO Fund incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Underlying PIMCO Fund might have been in a better position if the Underlying PIMCO Fund had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Underlying PIMCO Fund and its counterparty. Therefore, it may not be possible for an Underlying PIMCO Fund to modify, terminate, or offset the Underlying PIMCO Fund’s obligations or the Underlying PIMCO Fund’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Underlying PIMCO Fund. In such case, the Underlying PIMCO Fund may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, an Underlying PIMCO Fund may wish to retain the Underlying PIMCO Fund’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, an Underlying PIMCO Fund will be subject to increased liquidity and investment risk.

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When a derivative is used as a hedge against a position that an Underlying PIMCO Fund holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that an Underlying PIMCO Fund’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of an Underlying PIMCO Fund’s derivative transactions, impede the employment of the Underlying PIMCO Fund’s derivatives strategies, or adversely affect the Underlying PIMCO Fund’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Underlying PIMCO Funds' asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Underlying PIMCO Funds to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Underlying PIMCO Funds to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Underlying PIMCO Funds' ability to employ certain strategies that use these instruments and/or adversely affect the Underlying PIMCO Funds' performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Underlying PIMCO Funds' investments and cost of doing business, which could adversely affect investors.
Futures Contract Risk
A futures contract is an exchange-traded contract to buy or sell an underlying asset, such as a security, currency or commodity, for a set price on a future date. The risks associated with the Underlying PIMCO Fund’s use of derivative instruments, including futures contracts, are discussed in more detail under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and under “Investment Objectives and Policies” in the SAI. The purchase or sale of a futures contract may result in losses in excess of the amount invested in the futures contract. There can be no guarantee that there will be a correlation between price movements in the futures contract and the underlying asset. In addition, there are significant differences between the futures market and the markets for underlying assets, which could result in an imperfect correlation between the markets. The degree of imperfect correlation depends on circumstances such as variations in speculative market demand for futures and futures options on underlying assets, including technical influences in futures trading and futures options, and differences between the futures contract and underlying asset due to factors such as interest rate levels, maturities, and creditworthiness of issuers.
Futures contracts are traded on exchanges, so that, in most cases, a party can close out its position on the exchange for cash, without delivering the underlying asset. Because the futures utilized by certain Underlying PIMCO Funds are exchange-traded, the primary credit risk on futures contracts resides with the Underlying PIMCO Fund’s clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Underlying PIMCO Fund’s ability to invest in derivatives, limit an Underlying PIMCO Fund’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Underlying PIMCO Fund's performance. Futures exchanges may limit the amount of fluctuation permitted in certain futures contract prices during a single trading day. There can be no assurance that a liquid market will exist at a time when an Underlying PIMCO Fund seeks to close out a futures or a futures option position, and that the Portfolio or Underlying PIMCO Fund would remain obligated to meet margin requirements until the position is closed.
In addition, certain futures contracts may be relatively new instruments without a significant trading history. As a result, there can be no assurance that an active secondary market will develop or continue to exist.
Model Risk
In making investment allocation decisions for a Portfolio or certain Underlying PIMCO Funds, as applicable, PIMCO or the Sub-Adviser, as applicable, may utilize quantitative models that may be proprietary or developed by third-parties. These models are used by PIMCO or the Sub-Adviser, as applicable, to determine (or assist in determining) the Portfolio’s or Underlying PIMCO Fund’s target asset allocation and to identify potentially attractive relative value and risk hedging strategies. The investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in a Portfolio or Underlying PIMCO Fund. There can be no assurance that the models used by PIMCO or the Sub-Adviser, as applicable, will remain viable, due to various factors, which may include the quality of the data input into the models and the assumptions underlying such models, which to varying degrees involve the exercise of judgment, as well as the possibility of errors in constructing or using the model. In addition, in constructing the underlying index of, or model portfolio for, an Underlying PIMCO Fund that seeks to track the investment results of such underlying index or model portfolio, the index provider or sub-adviser, as applicable, may utilize quantitative models or

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Prospectus

methodologies that may be proprietary or developed by third-parties. These models and methodologies are used to help determine the composition of the underlying index or model portfolio and may not adequately take into account certain factors, resulting in a decline in the value of the underlying index or model portfolio and, therefore, the Underlying PIMCO Fund.
Models rely on accurate market data inputs. If inaccurate market data is entered into a model, the resulting information will be incorrect. In addition, the models used may be predictive in nature and such models may result in an incorrect assessment of future events. The models evaluate securities or securities markets based on certain assumptions concerning the interplay of market factors. The markets or the prices of individual securities may be affected by factors not foreseen in developing the models. In addition, when relying on a quantitative model and/or data supplied by third parties, PIMCO or the Sub-Adviser may have less insight into the construction, coding or testing of the third-party model or data, and PIMCO and the Sub-Adviser will be exposed to systems, cyber security and other risks associated with the third party that provides the model or data.
The use of models can be complex and involves financial, economic, econometric and statistical theories, research and modeling; and the results of those processes must then be translated into computer code. Although PIMCO and the Sub-Adviser seek to hire individuals and/or third parties, as applicable, skilled in each of these functions and to provide appropriate levels of oversight, the complexity of the individual tasks, the difficulty of integrating such tasks, and the limited ability to perform “real world” testing of a model’s end product raises the chances that a finished model may contain an error; one or more of such errors could adversely affect a Portfolio’s or an Underlying PIMCO Fund’s performance.
Commodity Risk
An Underlying PIMCO Fund’s investments in commodity-linked derivative instruments may subject the Underlying PIMCO Fund to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments. Certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund® , may each concentrate its assets in a particular sector of the commodities market (such as oil, metal or agricultural products). As a result, to the extent the Portfolio invests in the PIMCO CommoditiesPLUS® Strategy Fund or PIMCO CommodityRealReturn Strategy Fund® , each an Underlying PIMCO Fund, the Portfolio may be more susceptible to risks associated with those sectors. The prices for commodities in those sectors may fluctuate widely due to factors such as changes in value, supply and demand and governmental regulatory policies.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if an Underlying PIMCO Fund holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing an Underlying PIMCO Fund to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an Underlying PIMCO Fund to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of an Underlying PIMCO Funds because the Underlying PIMCO Fund may have to reinvest that money at the lower prevailing interest rates. An Underlying PIMCO Fund’s investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

April 30, 2021 | PROSPECTUS  13

PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
Certain Underlying PIMCO Funds may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than portfolios that invest exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers.
Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Underlying PIMCO Fund’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Underlying PIMCO Fund could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that an Underlying PIMCO Fund invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Underlying PIMCO Fund will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Real Estate Risk
Underlying PIMCO Funds that invest in real estate investment trusts (“REITs”) or real estate-linked derivative instruments are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. An investment in a REIT or a real estate-linked derivative instrument that is linked to the value of a REIT is subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (the “Code”). In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. Finally, private REITs are not traded on a national securities exchange. As such, these products are generally illiquid. This reduces the ability of an Underlying PIMCO Fund to redeem its investment early. Private REITs are also generally harder to value and may bear higher fees than public REITs
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent an Underlying PIMCO Fund invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, technical, political and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent an Underlying PIMCO Fund invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Underlying PIMCO Fund may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. An Underlying PIMCO Fund that focuses its investments in multiple asset classes of emerging marketsecurities may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. An Underlying PIMCO Fund may also be subject to Emerging Markets Risk if they invest in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Underlying PIMCO Funds could lose money the economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers of such emerging markets may be more affected by the performance of such industries or sectors..

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If an Underlying PIMCO Fund invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, an Underlying PIMCO Fund’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that an Underlying PIMCO Fund invests in foreign (non-U.S.)currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Issuer Non-Diversification Risk
Focusing investments in a small number of issuers increases risk. Underlying PIMCO Funds that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than Underlying PIMCO Funds that are “diversified.” Underlying PIMCO Funds that invest in a relatively small number of issuers are more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Some of those issuers also may present substantial credit or other risks.
To the extent that the Portfolio invests a significant portion of its assets in an Underlying PIMCO Fund, the Portfolio will be particularly sensitive to the risks associated with that Underlying PIMCO Fund. For a discussion of risks associated with Underlying PIMCO Funds, please see “Fund of Funds Risk” above.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate its leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. Underlying PIMCO Funds also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause an Underlying PIMCO Fund to liquidate portfolio positions to satisfy its obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause an Underlying PIMCO Fund to be more volatile than if the Underlying PIMCO Fund had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Underlying PIMCO Fund’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Underlying PIMCO Fund does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where an Underlying PIMCO Fund, for any reason, is unable to close out the transaction. In addition, to the extent an Underlying PIMCO Fund borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed an Underlying PIMCO Fund’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, an Underlying PIMCO Fund may be forced to sell portfolio securities when it is not otherwise advantageous to do so.

April 30, 2021 | PROSPECTUS  15

PIMCO Variable Insurance Trust

Smaller Company Risk
The general risks associated with fixed income securities and equity securities are particularly pronounced for securities issued by companies with smaller market capitalizations. These companies may have limited product lines, markets or financial resources or they may depend on a few key employees. As a result, they may be subject to greater levels of credit, market and issuer risk. Securities of smaller companies may trade less frequently and in lesser volumes than more widely held securities and their values may fluctuate more sharply than other securities. Companies with medium-sized market capitalizations may have risks similar to those of smaller companies.
Management Risk
Certain Underlying PIMCO Funds are subject to management risk because they are actively managed investment portfolios. PIMCO or the Sub-Adviser, as applicable, and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Underlying PIMCO Funds, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which an Underlying PIMCO Fund seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Underlying PIMCO Fund. To the extent the Underlying PIMCO Fund employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Underlying PIMCO Fund. Certain Underlying PIMCO Funds are also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Underlying PIMCO Fund or hinder Underlying PIMCO Fund operations. For example, trading delays or errors (both human and systematic) could prevent an Underlying PIMCO Fund from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Underlying PIMCO Funds and may also adversely affect the ability of the Underlying PIMCO Funds to achieve their investment objectives. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on an Underlying PIMCO Fund’s ability to realize its investment objective.
Because a number of Underlying PIMCO Funds obtain exposure to certain proprietary model stock portfolios by investing in equity total return swaps based on such model portfolios, in other securities and instruments to replicate the performance of such model portfolios, or directly in the equity securities held in such model portfolios, such Underlying PIMCO Funds will be subject to the risks associated with the management of these proprietary model stock portfolios by the sub-adviser to such Underlying PIMCO Funds. Similarly, there can be no assurance that quantitative models or methods utilized by PIMCO or the Sub-Adviser or related data sources will always be available, and the loss of access to any such model(s) or data sources could have an adverse impact on the Underlying PIMCO Fund's ability to realize its investment objective.
Short Exposure Risk
An Underlying PIMCO Fund’s short sales, if any, are subject to special risks. A short sale involves the sale by the Underlying PIMCO Fund of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. An Underlying PIMCO Fund may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Underlying PIMCO Fund will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, an Underlying PIMCO Fund could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase an Underlying PIMCO Fund’s exposure to long security positions and make any change in the Underlying PIMCO Fund’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy an Underlying PIMCO Fund employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, an Underlying PIMCO Fund may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Underlying PIMCO Fund.

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Risk
The PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund in which the Portfolio may invest, gain exposure to the commodities markets through investments in commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures. The PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund may also gain exposure indirectly to commodity markets by investing in their respective subsidiaries (the “Subsidiaries”), which invest primarily in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and/or other Fixed Income Instruments. In order for each Underlying PIMCO Fund to qualify as a regulated investment company under Subchapter M of the Code, the Underlying PIMCO Fund must derive at least 90 percent of its gross income each taxable year from certain qualifying sources of income.
As more fully described below under “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” the IRS issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. The IRS has issued private letter rulings in which the IRS specifically concluded that income derived from the Underlying PIMCO Fund’s investment in its Subsidiary will also constitute qualifying income to each Underlying PIMCO Fund. Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if an Underlying PIMCO Fund‘s income from an investment in the subsidiary is distributed annually or is derived with respect to the Underlying PIMCO Fund’s business of investing in securities. An IRS revenue procedure states that the IRS will issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the Investment Company Act of 1940, as amended (the “1940 Act”).
Each Underlying PIMCO Fund will seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in its respective Subsidiary. If the IRS were to determine that income derived from certain commodity-linked notes or from investments in the Subsidiary does not constitute qualifying income, the Portfolio and certain Underlying PIMCO Funds, including the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund, might be adversely affected and would be required to reduce their exposure to such investments which might result in difficulty in implementing their investment strategies and increased costs and taxes. The use of commodity index-linked notes and investments in the Subsidiaries involve specific risks. See “Characteristics and Risks of Securities and Investment Techniques-Derivatives-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” below for further information regarding commodity index-linked notes, including the risks associated with these instruments. In addition, see “Characteristics and Risks of Securities and Investment Techniques-Investments in a Wholly-Owned Subsidiary” below for further information regarding the Subsidiaries, including the risks associated with investing in the Subsidiaries.
To the extent the Portfolio invests in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund®, or PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, the use of the above noted investments by the Underlying PIMCO Fund could subject the shareholders of the Portfolio to risks similar to those borne by shareholders of the PIMCO CommodityRealReturn® Strategy and PIMCO Global Managed Asset Allocation Portfolios. See “Tax Consequences.”
Subsidiary Risk
By investing in their respective Subsidiaries, the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund, Underlying PIMCO Funds, are indirectly exposed to the risks associated with the respective Subsidiary’s investments. The investments held by the Subsidiaries are generally similar to those that are permitted to be held by these Underlying PIMCO Funds and are subject to the same risks that apply to similar investments if held directly by the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund or PIMCO TRENDS Managed Futures Strategy Fund. These risks are described elsewhere in this prospectus. There can be no assurance that the investment objectives of the Underlying PIMCO Funds or the Subsidiaries will be achieved.
The Subsidiaries are not registered under the 1940 Act, and, unless otherwise noted in this prospectus, are not subject to all the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund and/or the Subsidiaries to operate as described in this prospectus and the SAI and could adversely affect the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund and, to the extent the Portfolio invests in the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund, the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of an Underlying PIMCO Fund and/or a Subsidiary and result in the Underlying PIMCO Fund underperforming its benchmark index(es).

April 30, 2021 | PROSPECTUS  17

PIMCO Variable Insurance Trust

Value Investing Risk
Value investing attempts to identify companies that are believed to be undervalued. Value stocks typically have prices that are low relative to factors such as the company’s earnings, cash flow or dividends. A value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur. A value investing style may perform better or worse than equity portfolios that focus on growth stocks or that have a broader investment style.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.
Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
Exchange-Traded Fund (“ETF”) Risk
Investments in ETFs entail certain risks. Investments in ETFs designed to track an index involve the risk that the ETF’s performance may not track the performance of the index the ETF is designed to track. This deviation may occur due to cash inflows and outflows from and to investors buying and redeeming shares or due to occasional differences between the composition of the index and the securities held by the ETF. In addition, investments in ETFs involve the risk that the market prices of ETF shares will fluctuate, sometimes rapidly and materially, in response to changes in the ETF’s NAV, the value of ETF holdings and supply and demand for ETF shares. Although ETFs will generally trade close to NAV, market volatility, lack of an active trading market for ETF shares, disruptions at market participants (such as Authorized Participants or market makers) and any disruptions in the ordinary functioning of the creation/redemption process may result in ETF shares trading significantly above (at a “premium”) or below (at a “discount”) NAV. Significant losses may result when transacting in ETF shares in these and other circumstances.
Tracking Error Risk
An Underlying PIMCO Fund that seeks to track the investment results of an index may not invest in every component security of its underlying index. Imperfect correlation between an Underlying PIMCO Fund’s portfolio and its underlying index, asset valuation, timing variances, changes to the underlying index and regulatory requirements may cause the Underlying PIMCO Fund’s performance to diverge from the performance of its underlying index. Tracking error may also result because an Underlying PIMCO Fund incurs fees and expenses while its underlying index does not incur such fees and expenses. Such expenses include the costs of buying and selling securities, such as when an Underlying PIMCO Fund rebalances its portfolio to reflect changes in the composition of the underlying index. These expenses may be higher for an Underlying PIMCO Fund investing in foreign (non-U.S.) securities. The performance of an Underlying PIMCO Fund and the underlying index may vary due to differences between the Underlying PIMCO Fund’s portfolio and the underlying index due to legal restrictions, cost or liquidity restraints. The risk that performance of an Underlying PIMCO Fund and the underlying index may vary may be heightened during periods of market volatility or other unusual market conditions. Because an underlying index is not subject to the tax diversification requirements to which an Underlying PIMCO Fund must adhere, the Underlying PIMCO Fund may be required to deviate its investments from the securities and relative weightings of its underlying index. For tax efficiency purposes, an Underlying PIMCO Fund may sell certain securities to realize losses, which will result in a deviation from its underlying index. An Underlying PIMCO Fund may not be fully invested at times either as a result of cash flows into the Fund or reserves of cash held by the Fund to meet redemptions and to

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

pay expenses. In addition, if an Underlying PIMCO Fund uses a representative sampling approach, this approach may cause the Underlying PIMCO Fund to be less correlated with the return of the underlying index than if the Underlying PIMCO Fund held all of the securities in the underlying index with the same relative weightings as the underlying index.
Indexing Risk
Certain Underlying PIMCO Funds use an indexing approach and may be affected by a general decline in market segments or asset classes relating to their underlying indexes. Those Underlying PIMCO Funds invest in securities and instruments included in, or representative of, their underlying indexes regardless of the investment merits of the underlying indexes. Additionally, errors in the construction or calculation of an Underlying PIMCO Fund’s underlying index may occur from time to time, and the index provider may not identify or correct such errors for some period of time. Any such underlying index construction or calculation error may adversely impact the Underlying PIMCO Fund.
LIBOR Transition Risk
Certain instruments in which an Underlying PIMCO Fund may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on an Underlying PIMCO Fund or on certain instruments in which an Underlying PIMCO Fund invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of an Underlying PIMCO Fund's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by an Underlying PIMCO Fund or a reduction in the effectiveness of related Underlying PIMCO Fund transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of an Underlying PIMCO Fund that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to an Underlying PIMCO Fund.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

April 30, 2021 | PROSPECTUS  19

PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
PIMCO has engaged Research Affiliates, a California limited liability company (“Research Affiliates”), to serve as the asset allocation sub-adviser to the Portfolio. Research Affiliates was organized in 2002 and is located at 620 Newport Center Drive, Suite 900, Newport Beach, CA 92660. As asset allocation sub-adviser for the Portfolio, Research Affiliates is responsible for recommending how the assets of the Portfolio are allocated and reallocated from time to time among the Underlying PIMCO Funds.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.425% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.175% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract and asset allocation sub-advisory agreement is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) . PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.

20  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Fund of Funds Fees
The Portfolio is permitted to invest in Underlying PIMCO Funds, which, for the Portfolio, is defined to include the least expensive class of shares of any actively managed or smart beta funds (including mutual funds or exchange-traded funds) of PIMCO Funds, PIMCO ETF Trust or PIMCO Equity Series, each an affiliated open-end investment company, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. Shares of the PIMCO All Asset: Multi-Real Fund, PIMCO All Asset: Multi-RAE PLUS Fund and PIMCO All Asset: Multi-Short PLUS Fund (the “PAPS All Asset Funds”) may be purchased only by the Portfolio, as well as by the PIMCO All Asset Fund and PIMCO All Asset All Authority Fund, each a series of PIMCO Funds, an affiliated investment company. 
The Portfolio pays advisory fees directly to PIMCO at an annual rate of 0.175% based on the average daily net assets attributable in the aggregate to the Portfolio’s Administrative Class shares. The Portfolio pays supervisory and administrative fees directly to PIMCO at an annual rate of 0.25% based on the average daily net assets attributable in the aggregate to the Portfolio’s Administrative Class shares. The Portfolio also indirectly pays its proportionate share of the advisory, supervisory and administrative and management fees charged by PIMCO to the Underlying PIMCO Funds and, to the extent not included among the Underlying PIMCO Funds, funds of PIMCO ETF Trust in which the Portfolio invests (collectively, “Underlying PIMCO Fund Fees”).
PIMCO has contractually agreed, through May 1, 2022, to waive the Portfolio’s advisory fee to the extent that the Underlying PIMCO Fund Fees exceed 0.64% of the total assets invested in Underlying PIMCO Funds. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the advisory fee waived as set forth above (the “Asset Allocation Reimbursement Amount”) during the previous thirty-six months from the time of waiver, provided that such amount paid to PIMCO will not: 1) together with any Underlying PIMCO Fund Fees exceed, for such month, the applicable expense limit; 2) exceed the total Asset Allocation Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
The Acquired Fund Fees and Expenses shown in the Annual Portfolio Operating Expenses table for the Portfolio may be higher than the Underlying PIMCO Fund Fees used for purposes of the Expense Reduction shown in that table due to differences in the methods of calculation. The Acquired Fund Fees and Expenses, as required to be shown in the Annual Portfolio Operating Expenses table, are calculated using the total operating expenses for each Underlying PIMCO Fund over the Portfolio’s average net assets. The Underlying PIMCO Fund Fees that are used for purposes of implementing the expense reduction described above are calculated using the advisory and supervisory and administrative fees for each Underlying PIMCO Fund over the total assets invested in Underlying PIMCO Funds. Thus, the Acquired Fund Fees and Expenses listed in the Annual Portfolio Operating Expenses table will typically be higher than the Underlying PIMCO Fund Fees used to calculate the Expense Reduction when the Portfolio employs leverage as an investment strategy.
The expenses associated with investing in a fund of funds are generally higher than those for mutual funds that do not invest in other funds. The cost of investing in the Portfolio will generally be higher than the cost of investing in a portfolio that invests directly in individual stocks and bonds. By investing in the Portfolio, an investor may indirectly bear a portion of the fees and expenses charged by Underlying PIMCO Funds, to the extent such fees and expenses are not waived or reimbursed pursuant to applicable waiver and reimbursement agreements, in addition to the Portfolio’s direct fees and expenses. In addition, the use of a fund of funds structure could affect the timing, amount and character of distributions to shareholders and may therefore increase the amount of taxes payable by shareholders. The Portfolio invests in the least expensive class of shares of the Underlying PIMCO Funds, which are not subject to any sales charges or distribution (12b-1) fees.
The following table summarizes the annual expenses borne by Institutional Class or Class M shareholders of the Underlying PIMCO Funds (or, in the case of the PAPS All Asset Funds and those operating as exchange-traded funds, the Underlying PIMCO Fund shareholders). Because the Portfolio invests in the least expensive class of shares of the Underlying PIMCO Funds, shareholders of the Portfolio would indirectly bear a proportionate share of these expenses, depending upon how the Portfolio’s assets are allocated from time to time among the Underlying PIMCO Funds.
For a complete description of an Underlying PIMCO Fund, please see the Underlying PIMCO Fund’s Institutional Class or Class M prospectus or offering memorandum, as applicable. For a summary description of the Underlying PIMCO Funds, please see the “Descriptions of the Underlying PIMCO Funds” section in this prospectus.
Annual Underlying PIMCO Fund Expenses
(Based on the average daily net assets attributable to an Underlying PIMCO Fund’s Institutional Class shares (or Class M shares in the case of the PIMCO Government Money Market Fund , or the Fund in the case of the PAPS All Asset Funds and exchange-traded funds of the PIMCO ETF Trust or PIMCO Equity Series)).)).
Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO Active Bond Exchange-Traded Fund
0.55%
0.02%
0.57%
PIMCO All Asset: Multi-RAE PLUS Fund
0.89%
0.00%
0.89%

April 30, 2021 | PROSPECTUS  21

PIMCO Variable Insurance Trust

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO All Asset: Multi-Real Fund
0.74%
0.12%
0.86%(3)
PIMCO All Asset: Multi-Short PLUS Fund
0.74%
0.02%
0.76%(3)
PIMCO California Intermediate Municipal Bond Fund
0.445%
0.00%
0.445%
PIMCO California Municipal Bond Fund
0.44%
0.02%
0.46%
PIMCO California Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Climate Bond Fund
0.50%
0.00%
0.50%
PIMCO CommoditiesPLUS® Strategy Fund
0.74%
0.27%
1.01%(4)
PIMCO CommodityRealReturn Strategy Fund®
0.74%
0.76%
1.50%(5)
PIMCO Credit Opportunities Bond Fund
0.90%
0.02%
0.92%
PIMCO Diversified Income Fund
0.75%
0.04%
0.79%
PIMCO Dividend and Income Fund
0.75%
0.05%
0.80%(6)
PIMCO Dynamic Bond Fund
0.80%
0.05%
0.85%
PIMCO Emerging Markets Bond Fund
0.83%
0.05%
0.88%
PIMCO Emerging Markets Corporate Bond Fund
0.90%
0.12%
1.02%
PIMCO Emerging Markets Currency and Short-Term Investments Fund
0.85%
0.03%
0.88%
PIMCO Emerging Markets Local Currency and Bond Fund
0.90%
0.80%
1.70%
PIMCO Enhanced Low Duration Active Exchange-Traded Fund
0.46%
0.10%
0.56%
PIMCO Enhanced Short Maturity Active ESG Exchange-Traded Fund
0.36%
0.03%
0.39%(7)
PIMCO Enhanced Short Maturity Active Exchange-Traded Fund
0.35%
0.02%
0.37%
PIMCO ESG Income Fund
0.50%
0.07%
0.57%(8)
PIMCO Extended Duration Fund
0.50%
1.21%
1.71%
PIMCO Global Advantage® Strategy Bond Fund
0.65%
0.21%
0.86%
PIMCO Global Bond Opportunities Fund (U.S. Dollar-Hedged)
0.55%
0.04%
0.59%
PIMCO Global Bond Opportunities Fund (Unhedged)
0.55%
0.12%
0.67%
PIMCO GNMA and Government Securities Fund
0.50%
0.33%
0.83%
PIMCO Government Money Market Fund
0.18%
0.00%
0.18%(9)
PIMCO High Yield Fund
0.55%
0.02%
0.57%
PIMCO High Yield Municipal Bond Fund
0.55%
0.08%
0.63%
PIMCO High Yield Spectrum Fund
0.60%
0.02%
0.62%
PIMCO Income Fund
0.50%
0.59%
1.09%
PIMCO Intermediate Municipal Bond Active Exchange-Traded Fund
0.35%
0.00%
0.35%
PIMCO International Bond Fund (U.S. Dollar-Hedged)
0.50%
0.10%
0.60%
PIMCO International Bond Fund (Unhedged)
0.50%
0.13%
0.63%
PIMCO Investment Grade Credit Bond Fund
0.50%
0.35%
0.85%
PIMCO Long Duration Total Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term Credit Bond Fund
0.55%
0.29%
0.84%
PIMCO Long-Term Real Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term U.S. Government Fund
0.475%
1.38%
1.855%
PIMCO Low Duration Credit Fund(10)
0.70%
0.05%
0.75%
PIMCO Low Duration ESG Fund
0.50%
0.08%
0.58%
PIMCO Low Duration Fund
0.46%
0.41%
0.87%
PIMCO Low Duration Fund II
0.50%
0.03%
0.53%
PIMCO Low Duration Income Fund
0.50%
0.05%
0.55%
PIMCO Moderate Duration Fund
0.46%
0.15%
0.61%
PIMCO Mortgage Opportunities and Bond Fund
0.60%
1.22%
1.82%
PIMCO Mortgage-Backed Securities Fund
0.50%
0.25%
0.75%
PIMCO Municipal Bond Fund
0.44%
0.07%
0.51%
PIMCO National Intermediate Municipal Bond Fund
0.45%
0.00%
0.45%
PIMCO New York Municipal Bond Fund
0.445%
0.05%
0.495%
PIMCO Preferred and Capital Securities Fund
0.79%
0.09%
0.88%(11)
PIMCO RAE Emerging Markets Fund
0.75%
0.02%
0.77%(6)
PIMCO RAE Fundamental Advantage PLUS Fund
0.89%
0.07%
0.96%

22  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO RAE International Fund
0.50%
0.02%
0.52%(6)
PIMCO RAE PLUS EMG Fund
1.10%
0.21%
1.31%
PIMCO RAE PLUS Fund
0.79%
0.08%
0.87%
PIMCO RAE PLUS International Fund
0.82%
0.05%
0.87%
PIMCO RAE PLUS Small Fund
0.84%
0.09%
0.93%
PIMCO RAE US Fund
0.40%
0.02%
0.42%(6)
PIMCO RAE US Small Fund
0.50%
0.04%
0.54%
PIMCO RAE Worldwide Long/Short PLUS Fund
1.19%
0.09%
1.28%
PIMCO RAFI Dynamic Multi-Factor Emerging Markets Equity ETF
0.49%
0.01%
0.50%(12)
PIMCO RAFI Dynamic Multi-Factor International Equity ETF
0.39%
0.02%
0.41%(12)
PIMCO RAFI Dynamic Multi-Factor U.S. Equity ETF
0.29%
0.02%
0.31%(12)
PIMCO RAFI ESG U.S. ETF
0.29%
0.01%
0.30%
PIMCO Real Return Fund
0.45%
0.08%
0.53%
PIMCO RealEstateRealReturn Strategy Fund
0.74%
1.36%
2.10%
PIMCO Short Asset Investment Fund
0.34%
0.02%
0.36%
PIMCO Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Short Term Municipal Bond Active Exchange-Traded Fund
0.35%
0.00%
0.35%
PIMCO Short-Term Fund
0.45%
0.10%
0.55%
PIMCO StocksPLUS® Absolute Return Fund
0.64%
0.08%
0.72%
PIMCO StocksPLUS® Fund
0.50%
0.06%
0.56%
PIMCO StocksPLUS® International Fund (U.S. Dollar-Hedged)
0.75%
0.25%
1.00%
PIMCO StocksPLUS® International Fund (Unhedged)
0.64%
0.38%
1.02%
PIMCO StocksPLUS® Long Duration Fund
0.59%
0.42%
1.01%
PIMCO StocksPLUS® Short Fund
0.64%
0.45%
1.09%
PIMCO StocksPLUS® Small Fund
0.69%
0.06%
0.75%
PIMCO Strategic Bond Fund
0.55%
0.02%
0.57%(13)
PIMCO Total Return ESG Fund
0.50%
0.46%
0.96%
PIMCO Total Return Fund
0.46%
0.24%
0.70%
PIMCO Total Return Fund II
0.50%
0.26%
0.76%
PIMCO Total Return Fund IV
0.50%
0.30%
0.80%
PIMCO TRENDS Managed Futures Strategy Fund
1.40%
0.29%
1.69%(14)
1
“Management Fees” reflects an advisory fee and a supervisory and administrative fee payable by an Underlying PIMCO Fund to PIMCO.
2
Other Expenses include expenses such as organizational expenses, interest expense, taxes, governmental fees, pro rata Trustees' fees and acquired fund fees and expenses attributable to the Institutional Class or Class M shares or the Fund in the case of exchange-traded funds of the PIMCO ETF Trust or PIMCO Equity Series.
3
PIMCO has contractually agreed, through July 31, 2021, to waive a portion of the Fund’s supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Funds at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided certain conditions are met.
4
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund III Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
5
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund I Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
6
PIMCO has contractually agreed, through October 31, 2021, to waive a portion of the Fund's supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund's organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Equity Series at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.

April 30, 2021 | PROSPECTUS  23

PIMCO Variable Insurance Trust

7
PIMCO has contractually agreed, through October 31, 2022, to reduce its management fee by 0.12% of the average daily net assets of the Fund. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO ETF Trust at least 30 days prior to the end of the then current term. In any month in which the investment management agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the management fee waived as set forth above during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
8
PIMCO has contractually agreed, through July 31, 2022, to waive a portion of the Fund’s supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
9
To maintain certain net yields for the Fund, PIMCO or its affiliates may temporarily and voluntarily waive, reduce or reimburse all or any portion of the Fund's fees and expenses.
10
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund.
11
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Capital Securities Fund (Cayman) Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
12
PIMCO has contractually agreed, through October 31, 2021, to waive a portion of the Fund’s management fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Equity Series at least 30 days prior to the end of the then current term. In any month in which the investment management agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the management fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
13
PIMCO has contractually agreed, through July 31, 2021, to reduce its supervisory and administrative fee for each share class of the Fund by 0.05% of the average daily net assets attributable to the applicable class of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years from the date of waiver.
14
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund VIII, Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO All Asset
Robert D. Arnott
4/03*
Chairman and Founder, Research Affiliates, since July 2002. Previously, Mr. Arnott was
Chairman of First Quadrant, L.P. until April 2004. He first joined First Quadrant in April
1998.
PIMCO All Asset
Christopher J. Brightman
11/16
Chief Investment Officer, Research Affiliates, since April 2014. Previously at Research
Affiliates, Mr. Brightman served as a Managing Director and Head of Investment
Management. Prior to joining Research Affiliates in 2010, Mr. Brightman was chief
executive officer of the University of Virginia Investment Management Company.
*
Inception of the Portfolio.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.

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Prospectus

Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the 1940 Act, an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

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Prospectus

conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Underlying PIMCO Funds’ investment strategies may expose such Underlying PIMCO Funds to risks associated with market timing activities. For example, since some Underlying PIMCO Funds may invest in non-U.S. securities, they may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of an Underlying PIMCO Fund’s non-U.S. portfolio securities and the determination of the Underlying PIMCO Fund’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling fund shares at a price that does not reflect their true value. A similar risk exists for an Underlying PIMCO Fund’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
Except as identified below, to discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders (“Market Timing Policy”). Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders. In addition, purchases and sales by the Portfolio in certain Underlying PIMCO Funds may be exempt from certain limitations under the Market Timing Policy in order to allow the Portfolio to manage its cash flows and reallocate portfolio investments in the Underlying PIMCO Funds according to its allocation targets.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of

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such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio and Underlying PIMCO Fund shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or an Underlying PIMCO Fund or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
The assets of the Portfolio consist of shares of the Underlying PIMCO Funds, which are valued at their respective NAVs at the time of valuation of the Portfolio’s shares. For purposes of calculating the NAV of the Underlying PIMCO Funds, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security
traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of an Underlying PIMCO Fund’s assets that are invested in one or more open-end management investment companies, (other than exchange-traded funds), the Underlying PIMCO Fund’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a

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Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of an Underlying PIMCO Fund’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio invests in Underlying PIMCO Funds that hold foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Trustees or persons acting at their direction. The Trustees has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO.
Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of an Underlying PIMCO Fund’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When an Underlying PIMCO Fund uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by
another method that the Board of Trustees or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s and Underlying PIMCO Funds’ NAVs that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Underlying PIMCO Fund could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by an Underlying PIMCO Fund may differ from the value that would be realized if the securities were sold. An Underlying PIMCO Fund’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.The Portfolio may invest in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO

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CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund. One of the requirements for favorable tax treatment as a regulated investment company under the Code is that each Underlying PIMCO Fund derive at least 90% of its gross income from certain qualifying sources of income. The IRS has issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. As such, each Underlying PIMCO Fund’s ability to utilize commodity-linked swaps as part of its investment strategy is limited to a maximum of 10 percent of its gross income.
However, in a subsequent revenue ruling, the IRS provides that income from alternative investment instruments (such as certain commodity index-linked notes) that create commodity exposure may be considered qualifying income under the Code. The IRS has also issued a private letter ruling to the Underlying PIMCO Funds in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued another private letter ruling to each Underlying PIMCO Fund in which the IRS specifically concluded that income derived from the Underlying PIMCO Fund’s investment in its Subsidiary will also constitute qualifying income to the Underlying PIMCO Fund, even if the Subsidiary itself owns commodity linked swaps. Each Underlying PIMCO Fund will continue to seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in its Subsidiary.
Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if an Underlying PIMCO Fund‘s income from an investment in the subsidiary is derived with respect to the Underlying PIMCO Fund’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the 1940 Act. In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings. There can be no assurance that the IRS will not change its position with respect to some or all of these conclusions or that future legislation will not adversely impact the tax treatment of each Underlying PIMCO Fund’s commodity-linked investments. If the IRS were to change or reverse its position, or if future legislation adversely affected the tax treatment of the commodity-linked investments of each Underlying PIMCO Fund, there would likely be a significant adverse impact on the Underlying PIMCO Fund, including the possibility of failing to qualify as a regulated investment company. If an Underlying PIMCO Fund did not qualify as a regulated investment company for any taxable year, its taxable income would be subject to tax at the Underlying PIMCO Fund level at regular corporate tax rates (without reduction for distributions to shareholders) and to a further tax at the shareholder level when such income is distributed.
Furthermore, the tax treatment of commodity-linked notes, other commodity-linked derivatives, and an Underlying PIMCO Fund’s investments in its Subsidiary may otherwise be adversely affected by future legislation, court decisions, Treasury Regulations and/or guidance issued by the IRS. Such developments could affect the character, timing and/or amount of the Underlying PIMCO Fund’s taxable income or any distributions made by the Underlying PIMCO Fund or result in the inability of the Underlying PIMCO Fund to operate as described in its prospectus.
A Note on the PIMCO CommodityRealReturn Strategy Fund®, an Underlying PIMCO Fund.Periodic adjustments for inflation to the principal amount of an inflation-indexed bond may give rise to original issue discount, which will be includable in the Underlying PIMCO Fund’s gross income. Due to original issue discount, the Underlying PIMCO Fund may be required to make annual distributions to shareholders that exceed the cash received, which may cause the Underlying PIMCO Fund to liquidate certain investments when it is not advantageous to do so. Also, if the principal value of an inflation-indexed bond is adjusted downward due to deflation, amounts previously distributed in the taxable year may be characterized in some circumstances as a return of capital.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
The Portfolio invests substantially all of its assets in shares of the Underlying PIMCO Funds, and as such (unless otherwise noted) does not invest directly in the securities described below. The Underlying PIMCO Funds, however, may invest in such securities. Because the value of an investment in the Portfolio is directly related to the investment performance of the Underlying PIMCO Funds in which it invests, the risks of investing in the Portfolio are closely related to the risks associated with the Underlying PIMCO Funds and their investments in the securities described below. Please see the “Descriptions of the Underlying PIMCO Funds.”
This section provides additional information about some of the principal investments and related risks of the Portfolio and the Underlying PIMCO Funds described under the “Portfolio Summary,” “Description of Principal Risks” and “Descriptions of the Underlying PIMCO Funds.” It also describes characteristics and risks of additional securities and investment techniques that may be used by the Underlying PIMCO Funds from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Underlying PIMCO Funds. As with

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any mutual fund, investors in the Underlying PIMCO Funds rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Underlying PIMCO Funds.
Because the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, may each invest a portion of its assets in its respective Subsidiary, each of which may hold some of the investments described in this prospectus, each Underlying PIMCO Fund, and to the extent the Portfolio invests in each Underlying PIMCO Fund, the Portfolio, may be indirectly exposed to the risks associated with those investments. With respect to its investments, each Subsidiary will generally be subject to the same fundamental, non-fundamental and certain other investment restrictions as the respective Underlying PIMCO Fund; however, each Subsidiary (unlike the Underlying PIMCO Fund) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. Each Underlying PIMCO Fund and each Subsidiary may test for compliance with certain investment restrictions on a consolidated basis, except that with respect to its investments in certain securities that may involve leverage, the Subsidiary will comply with asset segregation or “earmarking” requirements to the same extent as its respective Underlying PIMCO Fund.
Investors should be aware that the investments made by a Portfolio and the results achieved by a Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to a Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact a Portfolio’s portfolio management. For example, a Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause Portfolios to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase a Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause a Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect a Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under
management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
Most of the Underlying PIMCO Funds seek maximum total return. The total return sought by an Underlying PIMCO Fund consists of both income earned on the Underlying PIMCO Fund’s investments and capital appreciation, if any, arising from increases in the market value of the Underlying PIMCO Fund’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation or improving credit fundamentals for a particular market sector or security.
In selecting securities for an Underlying PIMCO Fund, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Underlying PIMCO Fund’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors

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that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of
negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC

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certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Underlying PIMCO Fund to sell its bonds at attractive pries or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolios may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Underlying PIMCO Funds may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Underlying PIMCO Funds may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Underlying PIMCO Funds is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in
pre-refunded Municipal Bonds held by the Underlying PIMCO Funds may subject the Underlying PIMCO Funds to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if an Underlying PIMCO Fund sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
Certain Underlying PIMCO Funds may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that an Underlying PIMCO Fund investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.

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The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose an Underlying PIMCO Fund to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The value of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk.Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect an Underlying PIMCO Fund’s returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Underlying PIMCO Funds may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk.Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Underlying PIMCO Funds to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on an Underlying PIMCO Fund’s yield to maturity from these securities. Certain Underlying PIMCO Funds may invest up to 5% of their total assets in any combination of mortgage-related or other asset backed IO, PO or inverse floater securities.
An Underlying PIMCO Fund may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties.
Loan Participations and Assignments
Certain Underlying PIMCO Funds may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If an Underlying PIMCO Fund purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
An Underlying PIMCO Fund may be subject to the risk that the returns of the Underlying PIMCO Fund will decline during periods of falling interest rates because the Underlying PIMCO Fund may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Underlying PIMCO Fund’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Underlying PIMCO Fund to invest in lower-yielding securities. An Underlying PIMCO Fund also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Underlying PIMCO Fund’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by an Underlying PIMCO Fund from its investments is likely to have an adverse effect on the Underlying PIMCO Fund’s NAV, yield and total return.
Focused Investment
To the extent that an Underlying PIMCO Fund focuses its investments in a particular sector, the Underlying PIMCO Fund may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and

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other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, an Underlying PIMCO Fund may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Underlying PIMCO Fund to greater risk. An Underlying PIMCO Fund also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. Certain Underlying PIMCO Funds may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case an Underlying PIMCO Fund may lose its entire investment. The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue
high yield securities in which an Underlying PIMCO Fund may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. Each Underlying PIMCO Fund may invest in floating rate debt instruments (“floaters”) and certain Underlying PIMCO Funds may engage in credit spread trades. . A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Certain Underlying PIMCO Funds may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. Underlying PIMCO Funds that may invest in these securities may invest up to 5% of their total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, certain Underlying PIMCO Funds may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded

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deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Volatility
Volatility measures the variability in the price of an investment over time. A higher volatility level signifies an investment’s value may fluctuate over a larger range within a short period of time, either up or down. A lower volatility level means an investment’s value is more likely to change within a narrower range, or less frequently, over time. The more volatile the portfolio holdings of the Portfolio, the less predictable the returns for the Portfolio. Higher volatility levels may indicate heightened risk of losses.
PIMCO’s use of investments in seeking to manage the Portfolio‘s volatility will be consistent with the Portfolio’s asset allocation guidelines. Although asset allocation cannot eliminate investment risk or losses, it may provide opportunities to manage a Portfolio’s volatility relative to a Portfolio’s target annualized volatility level.
Event-Linked Exposure
Certain Underlying PIMCO Funds may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, an Underlying PIMCO Fund may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an
extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposures may also expose an Underlying PIMCO Fund to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposures may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
Certain Underlying PIMCO Funds may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. An Underlying PIMCO Fund may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Underlying PIMCO Fund’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. An Underlying PIMCO Fund may also purchase synthetic securities created by other parties, typically investment banks,

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including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, an Underlying PIMCO Fund may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for an Underlying PIMCO Fund.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time. In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to an Underlying PIMCO Fund as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, an Underlying PIMCO Fund may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, certain Underlying PIMCO Funds may determine or be required to accept equity securities, such as
common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by an Underlying PIMCO Fund at any given time upon sale thereof, an Underlying PIMCO Fund may determine to hold such securities in its portfolio.
While certain Underlying PIMCO Funds will generally invest in equity derivatives and will not normally invest directly in equity securities, each such Underlying PIMCO Fund may invest without limit directly in equity securities, including common stocks, preferred securities and convertible securities. In addition, the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, each an Underlying PIMCO Fund, may invest in equity securities of issuers in commodity-related industries, and the PIMCO RealEstateRealReturn Strategy Fund, an Underlying PIMCO Fund, may invest in REITs and equity securities of issuers in real estate-related industries. When investing directly in equity securities, an Underlying PIMCO Fund will not be limited to only those equity securities with any particular weighting in such Underlying PIMCO Fund’s respective benchmark index, if any. Generally, the Underlying PIMCO Funds will consider investing directly in equity securities when derivatives on the underlying securities appear to be overvalued.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by an Underlying PIMCO Fund may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
Certain Underlying PIMCO Funds may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instrument is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of

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exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, if the issuer of such money market instrument is organized under the laws of a non-U.S. country, or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Underlying PIMCO Funds that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruption, the possibility of security suspensions and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries’ financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments
in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers' financial reporting.
Certain of the Underlying PIMCO Funds also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.Certain Underlying PIMCO Funds may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries within the limitations, if any, set forth in each Underlying PIMCO Fund’s prospectus. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors, and the order in which they are applied may change in the discretion of PIMCO. The current factors listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test

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determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, an Underlying PIMCO Fund emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by an Underlying PIMCO Fund. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause an Underlying PIMCO Fund to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by
supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which an Underlying PIMCO Fund’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Underlying PIMCO Fund.
Foreign Currency Transactions.Underlying PIMCO Funds that invest in securities denominated in foreign (non-U.S.) currencies may engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Underlying PIMCO Fund’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Underlying PIMCO Fund is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Underlying PIMCO Fund’s ability to enter into foreign currency transactions, force the Underlying PIMCO Fund to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Underlying PIMCO Fund, any of which may result in a loss to the Underlying PIMCO Fund. A contract to sell a foreign currency would limit any potential gain which might be realized if the value of the hedged currency increases. An Underlying PIMCO Fund may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that an Underlying PIMCO Fund will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for an Underlying PIMCO Fund to benefit from favorable fluctuations in relevant foreign currencies. An Underlying PIMCO Fund may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Underlying PIMCO Fund will segregate or “earmark” assets determined to be liquid by PIMCO in accordance with the procedures established by the Board of

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Trustees (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of an Underlying PIMCO Fund’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, an Underlying PIMCO Fund’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. An Underlying PIMCO Fund may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if an Underlying PIMCO Fund earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Underlying PIMCO Fund’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio and each Underlying PIMCO Fund may enter into repurchase agreements, in which the Portfolio or the Underlying PIMCO Fund purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s or the Underlying PIMCO Fund’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio or the Underlying PIMCO Fund will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
Each Underlying PIMCO Fund may enter into reverse repurchase agreements and dollar rolls, subject to the Underlying PIMCO Fund’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by an Underlying PIMCO Fund and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Underlying PIMCO Fund but only securities that are “substantially identical.” Reverse repurchase
agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, an Underlying PIMCO Fund will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for an Underlying PIMCO Fund.
The Portfolio and Underlying PIMCO Funds may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio or Underlying PIMCO Fund may borrow money from banks for any purpose in an amount up to 1/3 of the Portfolio’s or Underlying PIMCO Fund’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio or Underlying PIMCO Fund may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s or Underlying PIMCO Fund’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
Certain Underlying PIMCO Funds may, but are not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). An Underlying PIMCO Fund may invest some or all of its assets in derivative instruments, subject to the Underlying PIMCO Fund’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by an Underlying PIMCO Fund will succeed. A description of these and other derivative instruments that the Underlying PIMCO Funds may use are described under “Investment Objectives and Policies” in the SAI.
An Underlying PIMCO Fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on an Underlying PIMCO Fund. For example, a small investment in a derivative instrument may have a significant impact on an Underlying PIMCO Fund’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. An Underlying PIMCO Fund may engage in such transactions regardless of whether the Underlying PIMCO Fund owns the asset, instrument or components of the index underlying the derivative instrument. An Underlying PIMCO Fund may invest a significant portion of its assets in these types of instruments. If it does, the Underlying PIMCO Fund’s investment exposure could far exceed the value of its

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portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Underlying PIMCO Funds.
CPI Swap. A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk. Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk. The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if an Underlying PIMCO Fund does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk. Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk. Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When an Underlying PIMCO Fund uses derivatives for leverage, investments in that Underlying PIMCO Fund will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Underlying PIMCO Fund will segregate or “earmark” assets
determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability. Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain an Underlying PIMCO Fund’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that an Underlying PIMCO Fund will engage in derivatives transactions at any time or from time to time. An Underlying PIMCO Fund’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk. In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, many of the Underlying PIMCO Funds seek to achieve their investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of these Underlying PIMCO Funds are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent an Underlying PIMCO Fund, or derivatives or other strategies used by the Underlying PIMCO Fund, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Underlying PIMCO Fund and the determination of the NAV value of Underlying PIMCO Fund shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Underlying PIMCO Fund invests; (iv) a fund having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of a fund (due to share purchases or redemptions, for example), potentially resulting in the Underlying PIMCO Fund being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Underlying PIMCO Fund’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.

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Market and Other Risks. Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to an Underlying PIMCO Fund’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for an Underlying PIMCO Fund, the Underlying PIMCO Fund might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Underlying PIMCO Fund investments. An Underlying PIMCO Fund may also have to buy or sell a security at a disadvantageous time or price because the Underlying PIMCO Fund is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Underlying PIMCO Fund’s derivative transactions, or impede the employment of the Underlying PIMCO Fund’s derivatives strategies, or adversely affect the Underlying PIMCO Fund’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to an Underlying PIMCO Fund. In addition, an Underlying PIMCO Fund’s use of derivatives may cause the Underlying PIMCO Fund to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Underlying PIMCO Fund had not used such instruments.
A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.The Portfolio may invest in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund. In light of releveant IRS guidance, as discussed above under “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” will seek to gain exposure to the commodity markets primarily through investments in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices, and through investments in its respective Subsidiary (as discussed below). The Underlying PIMCO Funds may also invest in commodity-linked notes with principal and/or coupon payments linked to the value of particular commodities or commodity futures contracts, or a subset of commodities and commodities futures contracts.
These notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in response to changes in the underlying commodity, commodity futures contract, subset of commodities, subset of commodities futures contracts or commodity index.
These notes expose the Underlying PIMCO Funds economically to movements in commodity prices. These notes also are subject to risks, such as credit, market and interest rate risks, that in general affect the values of debt securities. In addition, these notes are often leveraged, increasing the volatility of each note’s market value relative to changes in the underlying commodity, commodity futures contract or commodity index. Therefore, at the maturity of the note, the Underlying PIMCO Funds may receive more or less principal than it originally invested. The Underlying PIMCO Funds might receive interest payments on the note that are more or less than the stated coupon interest payments.
The Underlying PIMCO Funds may also invest in other commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures. The value of a commodity-linked derivative investment generally is based upon the price movements of a physical commodity (such as energy, mineral, or agricultural products), a commodity futures contract, a subset of commodities, a subset of commodities futures contracts or commodity index, or other economic variable based upon changes in the value of commodities or the commodities markets.
Options transactions may be effected on exchanges or in the OTC market. When OTC options are purchased, an Underlying PIMCO Fund’s portfolio bears the risk that the counterparty that wrote the option will be unable or unwilling to perform its obligations under the option contract. Options may also be illiquid and, in such cases, an Underlying PIMCO Fund may have difficulty closing out its position. OTC options also may include options on baskets of specific securities.
Many swap transactions are privately negotiated agreements between a fund and a counterparty to exchange or swap investment cash flows or assets at specified intervals in the future. The obligations may extend beyond one year. There is often no central exchange for swap transactions and therefore they can be less liquid investments than exchange-traded instruments. The Dodd-Frank Act and related regulatory developments require the clearing and exchange-trading of certain standardized OTC derivative instruments that the CFTC and SEC have defined as “swaps.” The CFTC has implemented mandatory exchange-trading and clearing requirements under the Dodd-Frank Act and the CFTC continues to approve contracts for central clearing. Uncleared swaps are subject to margin requirements that are being implemented on a phased-in basis. The investment adviser will continue to monitor these developments, particularly to the extent regulatory changes affect an Underlying PIMCO Fund’s ability to enter into swap agreements.
As described below under “Characteristics and Risks of Securities and Investment Techniques-Investments in a Wholly-Owned Subsidiary,” the Underlying PIMCO Funds may gain exposure to commodity markets by investing in their respective Subsidiaries. It is expected that each such

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Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments.
The IRS issued a revenue ruling that limits the extent to which the Underlying PIMCO Funds may invest directly in commodity-linked swaps or certain other commodity-linked derivatives. The Subsidiaries, on the other hand, may invest in these commodity-linked derivatives generally without limitation. See “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” above for further information.
Investments in a Wholly Owned Subsidiary
Investments in the Subsidiaries by the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, are expected to provide the Underlying PIMCO Funds with exposure to the commodity markets within the limitations of Subchapter M of the Code and recent IRS revenue rulings, as discussed above under “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.”
It is expected that each Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation indexed securities and other Fixed Income Instruments. Although the Underlying PIMCO Funds may enter into these commodity-linked derivative instruments directly, the Underlying PIMCO Funds will likely gain exposure to these derivative instruments indirectly by investing in the their respective Subsidiaries. To the extent that PIMCO believes that these commodity-linked derivative instruments are better suited to provide exposure to the commodities market than commodity index-linked notes, each Underlying PIMCO Fund’s investment in its respective Subsidiary will likely increase. Each Subsidiary will also invest in inflation-indexed securities and/or other Fixed Income Instruments, which are intended to serve as margin or collateral for the Subsidiary’s derivatives position, common and preferred securities as well as convertible securities of issuers in commodity-related industries, collateralized debt obligations, event-linked bonds and event-linked swaps. To the extent that an Underlying PIMCO Fund invests in its respective Subsidiary, it may be subject to the risks associated with those derivative instruments and other securities, which are discussed elsewhere in this prospectus.
While each Subsidiary may be considered similar to an investment company, it is not registered under the 1940 Act and, unless otherwise noted in each Underlying PIMCO Fund’s prospectus, is not subject to all of the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of an Underlying PIMCO Fund and/or a Subsidiary to operate as described in this prospectus and the SAI and could adversely affect an
Underlying PIMCO Fund as well as the Portfolio (to the extent the Portfolio invests in an Underlying PIMCO Fund). Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of an Underlying PIMCO Fund and/or a Subsidiary and result in the Underlying PIMCO Fund underperforming its benchmark index(es).
Real Estate Investment Trusts (REITs)
Certain Underlying PIMCO Funds may invest in REITs. REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
Certain Underlying PIMCO Funds may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in

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underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
Certain Underlying PIMCO Funds may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring an Underlying PIMCO Fund to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that an Underlying PIMCO Fund is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
Each Underlying PIMCO Fund may purchase or sell securities which it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Underlying PIMCO Fund’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Underlying PIMCO Fund’s overall investment exposure. Typically, no income accrues on securities that an Underlying PIMCO Fund has committed to purchase prior to the time delivery of the securities is made, although the Underlying PIMCO Fund may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio invests substantially all of its assets in other investment companies. The Portfolio’s investment in a particular Underlying PIMCO Fund normally will not exceed 50% of its total assets. An Underlying PIMCO Fund may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio and each Underlying PIMCO Fund may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Each Underlying PIMCO Fund may invest in securities of other investment companies, such as closed-end management investment companies including exchange-traded funds, or in pooled accounts or other investment vehicles which to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The limitation described in the foregoing sentence shall not apply to the investments of the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund in the Subsidiaries. As a shareholder of an investment company or other pooled vehicle, the Portfolio or Underlying PIMCO Funds may indirectly bear service and other fees which are in addition to the fees the Portfolio or Underlying PIMCO Funds pays its service providers.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, each Underlying PIMCO Fund may, in the future and the rules and regulations thereunder and any exemptive relief thereform, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Underlying PIMCO Fund.
Small-Cap and Mid-Cap Companies
Certain Underlying PIMCO Funds may invest in equity securities of small-capitalization and mid-capitalization companies, a small-cap company generally considered to be a company with a market

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capitalization of up to $1.5 billion and a mid-cap company generally considered to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Underlying PIMCO Fund’s investments in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
Each Underlying PIMCO Fund may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose an Underlying PIMCO Fund to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Underlying PIMCO Fund. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”), the Underlying PIMCO Fund must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that an Underlying PIMCO Fund contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. An Underlying PIMCO Fund may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent an Underlying PIMCO Fund engages in short selling in foreign (non-U.S.) jurisdictions, the Underlying PIMCO Fund will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
Each Underlying PIMCO Fund may invest up to 15% of its net assets (5% of total assets in the case of the PIMCO Government Money Market Fund) (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments, and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that an Underlying PIMCO Fund reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial
paper) may be treated as liquid (i.e., classified by an Underlying PIMCO Fund in a liquidity category other than “illiquid” pursuant to the Underlying PIMCO Fund’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, each Underlying PIMCO Fund may lend its portfolio securities to brokers, dealers, and other financial institutions provided a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When an Underlying PIMCO Fund lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Underlying PIMCO Fund will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. An Underlying PIMCO Fund may pay lending fees to a party arranging the loan. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time an Underlying PIMCO Fund has held a particular security is not generally a consideration in investment decisions. A change in the securities held by an Underlying PIMCO Fund is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, an Underlying PIMCO Fund may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Underlying PIMCO Fund’s portfolio) involves correspondingly greater expenses to an Underlying PIMCO Fund, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect an Underlying PIMCO Fund’s performance. Please see the Portfolio’s “Portfolio Summary – Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio and each Underlying PIMCO Fund may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities, in attempting

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to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio or Underlying PIMCO Fund engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s or an Underlying PIMCO Fund’s total net assets may be uninvested. In such cases, Portfolio or Underlying PIMCO Fund assets will be held in cash in the Portfolio’s or Underlying PIMCO Fund’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objectives of the Portfolio and certain Underlying PIMCO Funds are fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval. The investment objectives of certain Underlying PIMCO Funds may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio and Underlying PIMCO Fund investments listed in this prospectus will apply at the time of investment. The Portfolio and each Underlying PIMCO Fund would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. Certain Underlying PIMCO Funds have adopted a policy to invest at least 80% of their assets in investments suggested by their name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. An Underlying PIMCO Fund will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by an Underlying PIMCO Fund could receive a higher rating or a lower rating during the period in which they are held by an Underlying PIMCO Fund. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
An Underlying PIMCO Fund may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Underlying PIMCO Fund may purchase. In making ratings
determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that a portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Underlying PIMCO Fund invests in high yield and/or unrated securities, the Underlying PIMCO Fund’s success in achieving its investment objective may depend more heavily on the portfolio managers’ creditworthiness analysis than if the Underlying PIMCO Fund invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Underlying PIMCO Funds may invest in other types of securities and use a variety of investment techniques and strategies which are not described in this prospectus. These securities and techniques may subject the Underlying PIMCO Funds to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Underlying PIMCO Funds.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, sub-advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage;

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reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Descriptions of the Underlying PIMCO Funds
The Portfolio invests substantially all of its assets in some or all of the Underlying PIMCO Funds, which is defined to include the least expensive class of shares of any actively managed or smart beta funds (including mutual funds or exchange-traded funds) of PIMCO Funds, PIMCO ETF Trust or PIMCO Equity Series, each an affiliated open-end investment company, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. Shares of the PIMCO All Asset: Multi-Real Fund, PIMCO All Asset: Multi-RAE PLUS Fund and PIMCO All Asset: Multi-Short PLUS Fund (the “PAPS All Asset Funds”) may be purchased only by the Portfolio, as well as by the PIMCO All Asset Fund and PIMCO All Asset All Authority Fund, each a series of PIMCO Funds, an affiliated investment company. Because the Underlying PIMCO Funds are not offered in this prospectus, the following provides a general description of the main investments and other information about the Underlying PIMCO Funds. At the discretion of PIMCO and without shareholder approval, the Portfolio may invest in additional Underlying PIMCO Funds created in the future. For a complete description of an Underlying PIMCO Fund, please see that Fund’s Institutional Class or Class M prospectus (or Fund prospectus in the case of any exchange-traded fund of the PIMCO ETF Trust or PIMCO Equity Series, or Fund offering memorandum in the case of the PAPS All Asset Funds), which is incorporated herein by reference and is available free of charge by telephoning 1-800-927-4648.
Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Short Duration
PIMCO Low Duration Income
Short maturity fixed income instruments
0 to 3 years
Max 30% of total
assets below Baa(3)
No Limitation(4)
PIMCO Short Asset Investment
Money market instruments and short maturity
fixed income instruments
≤ 1.5 years
Baa to Aaa
0%
PIMCO Short-Term
Money market instruments and short maturity
fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below Baa
0-10% of total
assets(5)
PIMCO Low Duration
Short maturity fixed income instruments
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration II
Short maturity fixed income instruments with
quality and non-U.S. issuer restrictions
1 to 3 years
A to Aaa
0%
PIMCO Low Duration ESG
Short maturity fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration Credit(10)
Diversified portfolio of fixed income
instruments
0 to 3 years
Max 10% of total
assets below Caa
0-25% of total
assets(11)
Intermediate
Duration
PIMCO Moderate Duration
Short and intermediate maturity fixed income
instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO GNMA and Government
Securities
Short and intermediate maturity
mortgage-related fixed income securities issued
by the Government National Mortgage
Association and U.S. government securities
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa
0%
PIMCO High Yield
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(6); max
20% of total assets
Caa or below
0-20% of total
assets(5)
PIMCO High Yield Spectrum
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(7)
No Limitation(8)
PIMCO Mortgage-Backed Securities
Short and intermediate maturity
mortgage-related fixed income instruments
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa(9)
0%
PIMCO Total Return
Intermediate maturity fixed income instruments
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return II
Intermediate maturity fixed income instruments
with quality and non-U.S. issuer restrictions
+/-2 years of its
benchmark
Baa to Aaa
0%
PIMCO Total Return ESG
Intermediate maturity fixed income instruments
with prohibitions on firms engaged in socially
sensitive practices
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return IV
Intermediate maturity fixed income instruments
+/-1.5 years of its
benchmark
Baa to Aaa
0-15% of total
assets(11)
PIMCO Investment Grade Credit Bond
Investment grade fixed income securities
+/-2 years of its
benchmark
Max 15% of total
assets below Baa
0-30% of total
assets(5)

April 30, 2021 | PROSPECTUS  49

PIMCO Variable Insurance Trust

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Long Duration
PIMCO Long Duration Total Return
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Extended Duration
Long-term maturity fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO Long-Term U.S. Government
Long-term maturity fixed income securities
≥ 8 years
A to Aaa; max 25% Aa;
max 10% A
0%
PIMCO Mortgage Opportunities and
Bond
Mortgage-related assets and fixed income
instruments
(-1) to 8 years
Max 50% of total
assets below Baa(12)
0%
PIMCO Long-Term Credit Bond
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
B to Aaa; max 20% of
total assets below Baa
0-30% of total
assets(5)
Income
PIMCO ESG Income
Broad range of fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Income
Broad range of fixed income instruments
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Preferred and Capital Securities
Capital securities and preferred securities
+/-2 years of its
benchmark
No Limitation
No Limitation(4)
Inflation-Related
PIMCO Real Return
Inflation-indexed fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO Long-Term Real Return
Inflation-indexed fixed income securities
+/-4 years of its
benchmark
B to Aaa; max 20% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO CommoditiesPLUS® Strategy
Commodity-linked derivative instruments
backed by an actively managed low volatility
portfolio of fixed income instruments
≤ 1 year
Max 10% of total
assets below Baa
0-20%(4)
PIMCO CommodityRealReturn Strategy®
Commodity-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO RealEstateRealReturn Strategy
Real estate-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO All Asset: Multi-Real
Derivatives linked to real assets complemented
by a portfolio of inflation-linked securities and
other Fixed Income Instruments
≤ 10 years
B to Aaa; max 20%
below Baa(14)
0-30% of total
assets with respect
to the Fund’s
investments in
Fixed Income
Instruments(15)
Tax Exempt
PIMCO California Short Duration
Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal and California
income tax)
≤ 3 years
Caa to Aaa; max 10%
of total assets below
Baa
0%
PIMCO California Municipal Bond
Municipal securities (exempt from federal and
California income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO Short Duration Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal income tax)
≤ 3 years
Baa to Aaa
0%
PIMCO California Intermediate Municipal
Bond
Intermediate maturity municipal securities
(exempt from federal and California income
tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO National Intermediate Municipal
Bond
Municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO New York Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal and New York
income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO High Yield Municipal Bond
Intermediate to long-term maturity high yield
municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
No Limitation
0%

50  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
PIMCO Emerging Markets Bond
Emerging market fixed income instruments
+/- 2 years of its
benchmark
Max 15% of total
assets below B
≥ 80% of assets(16)
PIMCO Emerging Markets Currency and
Short-Term Investments
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and short-term investments
≤ 2 years
Max 15% of total
assets below B
No Limitation(17)
PIMCO International Bond
(U.S. Dollar-Hedged)
Intermediate maturity hedged non-U.S. fixed
income instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO International Bond (Unhedged)
Intermediate maturity non-U.S. fixed income
instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation
PIMCO Global Advantage® Strategy
Bond
U.S. and non-U.S. fixed income instruments
≤ 8 years
Max 15% of total
assets below B
No Limitation
PIMCO Global Bond Opportunities
(U.S. Dollar-Hedged)
U.S. and hedged non-U.S. intermediate maturity
fixed income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO Global Bond Opportunities
(Unhedged)
U.S. and non-U.S. intermediate maturity fixed
income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation
PIMCO Diversified Income
Investment grade corporate, high yield and
emerging market fixed income instruments
3 to 8 years
Max 10% below B
No Limitation
PIMCO Emerging Markets Local Currency
and Bond
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and fixed income instruments
+/-2 years of its
benchmark
Max 15% of total
assets below B
No Limitation(18)
PIMCO Emerging Markets Corporate
Bond
Diversified portfolio of fixed income
instruments economically tied to emerging
market countries
+/- 2 years of its
benchmark
Max 15% of total
assets below B
No Limitation
Absolute Return
PIMCO Dynamic Bond
Diversified portfolio of fixed income
instruments
(-3) to 8 years
Max 40% of total
assets below Baa
No Limitation(19)
PIMCO Strategic Bond
Diversified portfolio of fixed income
instruments
(-1) to 5 years
Max 20% of total
assets below Baa
No Limitation(20)
PIMCO Credit Opportunities Bond
Diversified portfolio of fixed income
instruments
0 to 6 years
Max 50% of total
assets below B-
No Limitation(5)
PIMCO TRENDS Managed Futures
Strategy
Financial and commodity-linked derivative
instruments selected by a quantitative strategy
and generally backed by a short to intermediate
duration portfolio which may consist of cash
equivalent securities and fixed income
instruments
N/A
No Limitation
No Limitation
PIMCO RAE Fundamental Advantage
PLUS
Long exposure to RAE US Large Model
Portfolio, short exposure to the S&P 500 Index,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO Climate Bond
Diversified portfolio of fixed income
instruments
2 to 8 years
Max 25% of total
assets below Baa
No Limitation(5)

April 30, 2021 | PROSPECTUS  51

PIMCO Variable Insurance Trust

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Domestic
Equity-Related
PIMCO RAE PLUS
Exposure to RAE US Large Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO StocksPLUS® Small
Russell 2000® Index derivatives backed by a
diversified portfolio of actively managed fixed
income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(21)
PIMCO StocksPLUS® Long Duration
S&P 500 Index derivatives backed by a
diversified portfolio of long-term fixed income
instruments
+/-2 years of
Bloomberg
Barclays
Long-Term
Government/Credit
Index(22)
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO StocksPLUS® Absolute Return
S&P 500 Index derivatives backed by a portfolio
of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS®
S&P 500 Index derivatives backed by a portfolio
of short-term fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO RAE PLUS Small
Exposure to RAE US Small Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE US
Exposure to RAE US Portfolio
N/A
N/A
0%
PIMCO RAE US Small
Exposure to RAE US Small Portfolio
N/A
N/A
0%
PIMCO RAFI ESG U.S. ETF
Component Securities of the RAFI ESG US Index
N/A
N/A
0%
PIMCO RAFI Dynamic Multi-Factor
U.S. Equity ETF
Component Securities of the RAFI Dynamic
multi-Factor US Index
N/A
N/A
0%
Equity-Related
PIMCO All Asset: Multi-RAE PLUS
Long exposure to a portfolio of stocks
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below Baa
(14)
No Limitation(21)
International
Equity-Related
PIMCO Dividend and Income
Exposure to RAE Income Global Portfolio in
Equity Sleeve; remainder of portfolio invests in
fixed income instruments of varying maturities
N/A
No Limitation
No Limitation
PIMCO RAE PLUS EMG
Exposure to RAE Emerging Markets Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(21)
PIMCO StocksPLUS® International
(Unhedged)
Non-U.S. equity derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(21)
PIMCO StocksPLUS® International
(U.S. Dollar-Hedged)
Non-U.S. equity derivatives (hedged to
U.S. dollars) backed by a portfolio of fixed
income instruments.
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(21)
PIMCO RAE PLUS International
Exposure to RAE International Large Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(11)
PIMCO RAE Worldwide Long/Short PLUS
Long exposure to RAE Low Volatility U.S. Model
Portfolio, RAE Low Volatility Intl Model Portfolio
and RAE Low Volatility EMG Model Portfolio,
short exposure to certain traditional
capitalization-weighted equity indexes,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(11)
PIMCO RAE Emerging Markets
Exposure to RAE Emerging Markets Portfolio
N/A
N/A
No Limitation
PIMCO RAE International
Exposure to RAE International Portfolio
N/A
N/A
No Limitation
PIMCO RAFI Dynamic Multi-Factor
Emerging Markets Equity ETF
Component securities of the RAFI Dynamic
Multi-Factor Emerging Markets Index
N/A
N/A
No Limitation
PIMCO RAFI Dynamic Multi-Factor
International Equity ETF
Component securities of the RAFI Dynamic
Multi-Factor Developed Ex-U.S. Index
N/A
N/A
No Limitation
U.S. Government
Securities
PIMCO Government Money Market
U.S. government securities
≤ 60 days
dollar-weighted
average maturity
Min 97% of total
assets Prime 1; ≤ 3%
of total assets Prime 2
0%

52  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Short Strategies
PIMCO StocksPLUS® Short
Short S&P 500 Index derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO All Asset: Multi-Short PLUS
Short exposure to equity markets
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below Baa
(14)
No Limitation(21)
Actively-Managed
Exchange-Traded
Funds
PIMCO Active Bond Exchange-Traded
Fixed income instruments of varying maturities
2 to 8 years
Max 30% of total
assets below Baa
0-15% of total
assets(4)
PIMCO Enhanced Low Duration Active
Exchange-Traded
Fixed income instruments of varying maturities
1 to 3 years
Max 15% below Baa
No Limitation(11)
PIMCO Enhanced Short Maturity Active
Exchange-Traded
Short to intermediate maturity fixed income
instruments
≤1 year
Baa to Aaa
0%
PIMCO Intermediate Municipal Bond
Active Exchange-Traded
Intermediate maturity municipal securities
(exempt from federal income tax)
(-2) to 4 years of
its benchmark
Baa to Aaa
0%
PIMCO Short Term Municipal Bond Active
Exchange-Traded
Short maturity municipal securities (exempt
from federal income tax)
≤ 3 years
Baa to Aaa
0%
PIMCO Enhanced Short Maturity Active
ESG Exchange-Traded
Short to intermediate maturity fixed income
instruments
≤1 year
Baa to Aaa
0-10% of total
assets
1
As rated by Moody's, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality.
2
Certain Underlying PIMCO Funds may invest beyond these limits in U.S. dollar-denominated instruments of non-U.S. issuers.
3
Such limitation shall not apply to the Fund's investments in mortgage- and asset-backed securities.
4
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 10% of its total assets.
5
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
6
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index.
7
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML Developed Markets High Yield Constrained (USD Hedged) Index.
8
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to within 10% (plus or minus) of the Fund's benchmark's foreign currency exposure.
9
The Fund may also invest up to an additional 5% of its total assets in mortgage-related high yield instruments rated below Baa.
10
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund. Information for the PIMCO Low Duration Credit Fund is effective as of May 3, 2021.
11
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 5% of its total assets.
12
Such limitation shall not apply to the Fund's investments in mortgage-related securities.
13
Within such limitation, the Fund may invest in mortgage-related securities rated below B.
14
Within such limitation, the Fund may invest in mortgage- and asset-backed securities rated below B.
15
With respect to the Fund's fixed income investments, the Fund will normally limit its foreign currency exposure (from non-U.S. dollar denominated securities or currencies) to 20% of its total assets.
16
The percentage limitation relates to Fixed Income Instruments of non-U.S. issuers denominated in any currency.
17
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or in Fixed Income Instruments denominated in the currencies of, emerging market countries, and in short-term investments.
18
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or Fixed Income Instruments denominated in the currencies of, emerging market countries and in Fixed Income Instruments, each of which may be represented by forwards or derivatives such as options, futures contracts or swap agreements.
19
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
20
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 25% of its total assets.
21
With respect to the Fund's fixed income investments, the Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
22
The Bloomberg Barclays Long-Term Government/Credit Index is an unmanaged index of U.S. Government or investment grade credit securities having a maturity of 10 years or more.

April 30, 2021 | PROSPECTUS  53

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO All Asset Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$10.79
$0.39
$0.40
$0.79
$(0.51)
$0.00
$0.00
$(0.51)
12/31/2019
9.93
0.33
0.84
1.17
(0.31)
0.00
0.00
(0.31)
12/31/2018
10.85
0.48
(1.06)
(0.58)
(0.34)
0.00
0.00
(0.34)
12/31/2017
10.01
0.47
0.87
1.34
(0.48)
0.00
(0.02)
(0.50)
12/31/2016
9.10
0.22
0.95
1.17
(0.24)
0.00
(0.02)
(0.26)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratios shown do not include expenses of the investment companies in which the Portfolio may invest. See the Fees and Expenses note in the Notes to Financial Statements for more information regarding the expenses and any applicable fee waivers associated with these investments.
(e)
Includes in-kind purchases and sales of underlying funds. Please see Investments in Securities, note in the Notes to Financial Statements for more information.

54  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets(d)
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.07
8.01%
$381,112
0.475%
0.575%
0.475%
0.575%
3.85%
(e)141%
10.79
11.90
426,305
0.425
0.575
0.425
0.575
3.14
31
9.93
(5.41)
444,136
0.455
0.575
0.455
0.575
4.56
37
10.85
13.54
554,749
0.475
0.575
0.475
0.575
4.46
40
10.01
12.93
537,663
0.425
0.575
0.425
0.575
2.23
67

April 30, 2021 | PROSPECTUS  55

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0328F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
Active Asset Allocation Portfolio – Real Return Oriented
PIMCO All Asset Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO All Asset Portfolio

Investment Objective
The Portfolio seeks maximum real return, consistent with preservation of real capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.425%
Distribution and/or Service (12b-1) Fees
0.25%
Acquired Fund Fees and Expenses(1)
0.80%
Total Annual Portfolio Operating Expenses(2)
1.475%
Fee Waiver and/or Expense Reimbursement(3)
(0.10%)
Total Annual Portfolio Operating Expenses After Fee Waiver and/or
Expense Reimbursement
1.375%
1
Acquired Fund Fees and Expenses include interest expense of the Underlying PIMCO Funds of 0.06%. Interest expense can result from certain transactions within the Underlying PIMCO Funds and is separate from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense of the Underlying PIMCO Funds, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 1.315% for Advisor Class shares.
2
Total Annual Portfolio Operating Expenses do not match the Ratio of Expenses to Average Net Assets Excluding Waivers of the Portfolio, as set forth in the Financial Highlights table of the Portfolio’s prospectus, because the Ratio of Expenses to Average Net Assets Excluding Waivers reflects the operating expenses of the Portfolio and does not include Acquired Fund Fees and Expenses.
3
PIMCO has contractually agreed, through May 1, 2022, to reduce its advisory fee to the extent that the Underlying PIMCO Fund Expenses attributable to advisory and supervisory and administrative fees exceed 0.64% of the total assets invested in Underlying PIMCO Funds. PIMCO may recoup these waivers in future periods, not exceeding three years from the date of waiver, provided total expenses, including such recoupment, do not exceed the annual expense limit that was in place at the time the amount being recouped was originally waived and the current annual expense limit. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. The fee reduction is implemented based on a calculation of Underlying PIMCO Fund Expenses attributable to advisory and supervisory and administrative fees that is different from the calculation of Acquired Fund Fees and Expenses listed in the table above.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these
assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$140
$457
$796
$1,754
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 141% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio is a “fund of funds,” which is a term used to describe mutual funds that pursue their investment objective by investing in other funds. The Portfolio seeks to achieve its investment objective by investing under normal circumstances substantially all of its assets in the least expensive class of shares of any actively managed or smart beta funds (including mutual funds or exchange-traded funds) of PIMCO Funds, PIMCO ETF Trust or PIMCO Equity Series, each an affiliated open-end investment company, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management (collectively, “Underlying PIMCO Funds”). As used in the investment objective, “real return” equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure, and “real capital” equals capital less the estimated cost of inflation measured by the change in an official inflation measure. In addition to investing in Underlying PIMCO Funds, at the discretion of PIMCO and without shareholder approval, the Portfolio may invest in additional Underlying PIMCO Funds created in the future.
The Portfolio invests its assets in shares of the Underlying PIMCO Funds and does not invest directly in stocks or bonds of other issuers. Research Affiliates, the Portfolio’s asset allocation sub-adviser, determines how the Portfolio allocates and reallocates its assets among the Underlying PIMCO Funds. In doing so, the asset allocation sub-adviser seeks concurrent exposure to a broad spectrum of asset classes.
Investments in Underlying PIMCO Funds.The Portfolio may invest in any or all of the Underlying PIMCO Funds, but will not normally invest in every Underlying PIMCO Fund at any particular time. The Portfolio’s investment in a particular Underlying PIMCO Fund normally will not exceed 50% of its total assets. The Portfolio will not invest in the Short Strategy Underlying PIMCO Funds, which seek to gain a negative exposure to an asset class such as equities. The Portfolio’s combined investments in the Equity-Related Underlying PIMCO Funds will not exceed 50% of its total assets. In addition, the Portfolio’s combined investments in Inflation-Related Underlying PIMCO Funds, which seek to gain exposure to an asset class such as U.S. Treasury

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Inflation-Protected Securities (“TIPS”), commodities, or real estate, normally will not exceed 75% of its total assets.
Asset Allocation Investment Process.The Portfolio’s assets are not allocated according to a predetermined blend of shares of the Underlying PIMCO Funds. Instead, when making allocation decisions among the Underlying PIMCO Funds, the Portfolio’s asset allocation sub-adviser considers various quantitative and qualitative data relating to the U.S. and foreign economies and securities markets. Such data includes projected growth trends in the U.S. and foreign economies, forecasts for interest rates and the relationship between short- and long-term interest rates (yield curve), current and projected trends in inflation, relative valuation levels in the equity and fixed income markets and various segments within those markets, the outlook and projected growth of various industrial sectors, information relating to business cycles, borrowing needs and the cost of capital, political trends, data relating to trade balances and labor information. The Portfolio’s asset allocation sub-adviser has the flexibility to reallocate the Portfolio’s assets among any or all of the asset class exposures represented by the Underlying PIMCO Funds based on its ongoing analyses of the equity, fixed income and commodity markets. While these analyses are performed daily, material shifts in asset class exposures typically take place over longer periods of time.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Principal Risks of the Portfolio
Allocation Risk:the risk that a Portfolio could lose money as a result of less than optimal or poor asset allocation decisions. The Portfolio could miss attractive investment opportunities by underweighting markets that subsequently experience significant returns and could lose value by overweighting markets that subsequently experience significant declines
Fund of Funds Risk:the risk that a Portfolio’s performance is closely related to the risks associated with the securities and other investments held by the Underlying PIMCO Funds and that the ability of a Portfolio to achieve its investment objective will depend upon the ability of the Underlying PIMCO Funds to achieve their investment objectives
Certain principal risks of investing in the Underlying PIMCO Funds, and consequently the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Certain Principal Risks of Underlying PIMCO Funds
Market Trading Risk:the risk that an active secondary trading market for shares of an Underlying PIMCO Fund that is an exchange-traded fund does not continue once developed, that such Underlying PIMCO Fund may not continue to meet a listing exchange’s trading or listing requirements, or that such Underlying PIMCO Fund’s shares trade at prices other than the Fund’s net asset value
Municipal Project-Specific Risk:the risk that an Underlying PIMCO Fund may be more sensitive to adverse economic, business or political developments if it invests a substantial portion of its assets in the bonds of specific projects (such as those relating to education, health care, housing, transportation, and utilities), industrial development bonds, or in bonds from issuers in a single state
Municipal Bond Risk:the risk that an Underlying PIMCO Fund may be affected significantly by the economic, regulatory or political developments affecting the ability of issuers of debt securities whose interest is, in the opinion of bond counsel for the issuer at the time of issuance, exempt from federal income tax (“Municipal Bonds”) to pay interest or repay principal
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Distressed Company Risk:the risk that securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services

April 30, 2021 | PROSPECTUS  2

PIMCO All Asset Portfolio

Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. An Underlying PIMCO Fund’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Underlying PIMCO Fund’s ability to invest in derivatives, limit the Underlying PIMCO Fund’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Underlying PIMCO Fund’s performance
Futures Contract Risk:the risk that, while the value of a futures contract tends to correlate with the value of the underlying asset that it represents, differences between the futures market and the market for the underlying asset may result in an imperfect correlation. Futures contracts may involve risks different from, and possibly greater than, the risks associated with investing directly in the underlying assets. The purchase or sale of a futures contract may result in losses in excess of the amount invested in the futures contract
Model Risk:the risk that an Underlying PIMCO Fund’s investment models used in making investment allocation decisions, and the indexation methodologies used in constructing an underlying index for an Underlying PIMCO Fund that seeks to track the investment results of such underlying index, may not adequately take into account certain factors and may result in a decline in the value of an investment in the Underlying PIMCO Fund
Commodity Risk:the risk that investing in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or
factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Real Estate Risk:the risk that the Portfolio’s investments in Real Estate Investment Trusts (“REITs”) or real estate-linked derivative instruments will subject the Portfolio to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. A Portfolio’s investments in REITs or real estate-linked derivative instruments subject it to management and tax risks. In addition, privately traded REITs subject a Portfolio to liquidity and valuation risk
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Smaller Company Risk:the risk that the value of securities issued by a smaller company may go up or down, sometimes rapidly and unpredictably as compared to more widely held securities, due to narrow markets and limited resources of smaller companies. A Portfolio’s investments in smaller companies subject it to greater levels of credit, market and issuer risk
Issuer Non-Diversification Risk:the risk of focusing investments in a small number of issuers, including being more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Portfolios that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified”
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO, or Research Affiliates, and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO or Research Affiliates to restrict or prohibit participation in certain investments.. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Tax Risk:the risk that the tax treatment of swap agreements and other derivative instruments, such as commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures, may be affected by future regulatory or legislative changes that could affect whether income from such investments is “qualifying income” under Subchapter M of the Internal Revenue Code, or otherwise affect the character, timing and/or amount of the Portfolio’s taxable income or gains and distributions
Subsidiary Risk:the risk that, by investing in certain Underlying PIMCO Funds that invest in a subsidiary (each a “Subsidiary”), the Portfolio is indirectly exposed to the risks associated with a Subsidiary’s investments. The Subsidiaries are not registered under the 1940 Act and may not be subject to all the investor protections of the 1940 Act. There is no guarantee that the investment objective of a Subsidiary will be achieved
Value Investing Risk:a value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
Exchange-Traded Fund Risk:the risk that an exchange-traded fund may not track the performance of the index it is designed to track, among other reasons, because of exchange rules, market prices of shares of an exchange-traded fund may fluctuate rapidly and materially, or shares of an exchange-traded fund may trade significantly above or below net asset value, any of which may cause losses to the Portfolio invested in the exchange-traded fund
Tracking Error Risk:the risk that the portfolio of an Underlying PIMCO Fund that seeks to track the investment results of an underlying index may not closely track the underlying index for a number of reasons. The Underlying PIMCO Fund incurs operating expenses, which are not applicable to the underlying index, and the costs of buying and selling securities, especially when rebalancing the Underlying PIMCO Fund’s portfolio to reflect changes in the composition of the underlying index. Performance of the Underlying PIMCO Fund and the underlying index may vary due to asset valuation differences and differences between the Underlying PIMCO Fund’s portfolio and the underlying index due to legal restrictions, cost or liquidity restraints. The risk that performance of the Underlying PIMCO Fund and the underlying index may vary may be heightened during periods of increased market volatility or other unusual market conditions. In addition, an Underlying PIMCO Fund’s use of a representative sampling approach may cause the Underlying PIMCO Fund to be less correlated to the return of the underlying index than if the Underlying PIMCO Fund held all of the securities in the underlying index
Indexing Risk:the risk that an Underlying PIMCO Fund that seeks to track the investment results of an underlying index is negatively affected by general declines in the asset classes represented by the underlying index
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by an Underlying PIMCO Fund rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Underlying PIMCO Fund or on certain instruments in which the Underlying PIMCO Fund invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in value of certain instruments held by the Underlying PIMCO Fund
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

April 30, 2021 | PROSPECTUS  4

PIMCO All Asset Portfolio

Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index and an index of similar funds. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio measures its performance against a primary benchmark and a secondary benchmark. The Bloomberg Barclays U.S. TIPS: 1-10 Year Index, the primary benchmark, is an unmanaged index comprised of U.S. Treasury Inflation-Protected securities having a maturity of at least 1 year and less than 10 years. The CPI + 500 Basis Points benchmark, the secondary benchmark, is created by adding 5% to the annual percentage change in the Consumer Price Index (“CPI”). The CPI is an unmanaged index representing the rate of inflation of the U.S. consumer prices as determined by the U.S. Bureau of Labor Statistics.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
June 30, 2020
12.15%
Worst Quarter
March 31, 2020
-16.21%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Advisor Class Return
7.91%
7.85%
4.54%
Bloomberg Barclays U.S. TIPS: 1-10 Year Index (reflects
no deductions for fees, expenses or taxes)
8.39%
4.13%
2.88%
Consumer Price Index + 500 Basis Points (reflects no
deductions for fees, expenses or taxes)
6.29%
6.94%
6.73%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. Research Affiliates serves as the asset allocation sub-adviser to the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Robert D. Arnott and Christopher J. Brightman. Mr. Arnott is the Chairman and Founder of Research Affiliates and he has managed the Portfolio since its inception in April 2003. Mr. Brightman is Chief Investment Officer of Research Affiliates and he has managed the Portfolio since November 2016.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

5  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments in the Underlying PIMCO Funds. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Underlying PIMCO Funds, and consequently the Portfolio, are identified in the Portfolio Summary and are described in this section. The Portfolio and the Underlying PIMCO Funds may be subject to additional risks other than those identified and described below because the types of investments made by an Underlying PIMCO Fund can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Underlying PIMCO Funds, their investments and the related risks. There is no guarantee that the Portfolio or the Underlying PIMCO Funds will be able to achieve their investment objectives. It is possible to lose money by investing in the Portfolio.
Allocation Risk
The Portfolio’s investment performance depends upon how its assets are allocated and reallocated between the Underlying PIMCO Funds according to the Portfolio’s asset allocation targets and ranges. A principal risk of investing in the Portfolio is that the asset allocation sub-adviser will make less than optimal or poor asset allocation decisions. The asset allocation sub-adviser attempts to identify investment allocations for the Underlying PIMCO Funds that will provide consistent, quality performance for the Portfolio, but there is no guarantee that such allocation techniques will produce the desired results. It is possible that the asset allocation sub-adviser will focus on an Underlying PIMCO Fund that performs poorly or underperforms other Underlying PIMCO Funds under various market conditions. You could lose money on your investment in the Portfolio as a result of these allocation decisions.
Fund of Funds Risk
Because the Portfolio invests substantially all of its assets in Underlying PIMCO Funds, the risks associated with investing in the Portfolio are closely related to the risks associated with the securities and other investments held by the Underlying PIMCO Funds. The ability of the Portfolio to achieve its investment objective will depend upon the ability of the Underlying PIMCO Funds to achieve their respective investment objectives. There can be no assurance that the investment objective of any Underlying PIMCO Fund will be achieved.
The Portfolio’s net asset value (“NAV”) will fluctuate in response to changes in the respective NAVs of the Underlying PIMCO Funds in which it invests. The extent to which the investment performance and risks associated with the Portfolio correlate to those of a particular Underlying PIMCO Fund will depend upon the extent to which the Portfolio’s assets are allocated from time to time for investment in the Underlying PIMCO Fund, which will vary. To the extent that the Portfolio invests a significant portion of its assets in an Underlying PIMCO Fund, it will be particularly sensitive to the risks associated with that Underlying PIMCO Fund.
Market Trading Risk
An Underlying PIMCO Fund that is an exchange-traded fund is subject to secondary market trading risks. Once operational, shares of the Underlying PIMCO Fund are listed for trading on an exchange, however, there can be no guarantee that an active trading market for such shares will develop or continue. Shares of the Underlying PIMCO Fund may be listed or traded on U.S. and foreign (non-U.S.) exchanges other than the Underlying PIMCO Fund’s primary U.S. listing exchange. There can be no guarantee that the Underlying PIMCO Fund’s shares will continue trading on any exchange or in any market or that the Underlying PIMCO Fund’s shares will continue to meet the listing or trading requirements of any exchange or market. The Underlying PIMCO Fund’s shares may experience higher trading volumes on one exchange as compared to another and investors are subject to the execution and settlement risks of the market where their broker directs trades.
Secondary market trading in the Underlying PIMCO Fund’s shares may be halted by an exchange because of market conditions. Pursuant to exchange or market rules, trading in the Underlying PIMCO Fund’s shares on an exchange or in any market may be subject to trading halts caused by extraordinary market volatility. If secondary market trading is halted or an exchange closes earlier than anticipated, you may be unable to purchase or sell Portfolio shares. There can be no guarantee that the Underlying PIMCO Fund’s exchange listing or ability to trade its shares will continue or remain unchanged. In the event the Underlying PIMCO Fund ceases to be listed on an exchange, the Underlying PIMCO Fund may cease operating as an “exchange-traded” fund and operate as a mutual fund, provided that shareholders are given advance notice.
Buying or selling the Underlying PIMCO Fund’s shares on an exchange may require the payment of brokerage commissions. In addition, an investor who buys or sells the Underlying PIMCO Fund’s shares may also incur the cost of the spread (the difference between the bid price and the ask price). The commission is frequently a fixed amount and may be a significant cost for investors seeking to buy or sell small amounts of shares. The spread varies over time for shares of the Underlying PIMCO Fund based on their trading volume and market liquidity, and is generally less if the Underlying PIMCO Fund has more trading volume and market liquidity and more if the Underlying PIMCO Fund has less trading volume and market liquidity. Due to the costs inherent in buying or selling the Underlying PIMCO Fund’s shares, frequent trading may detract significantly from investment returns. Investment in the Underlying PIMCO Fund’s shares may not be advisable for investors who expect to engage in frequent trading.

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Shares of the Underlying PIMCO Fund may trade on an exchange at prices at, above or below their most recent NAV. The market prices of an Underlying PIMCO Fund’s shares will fluctuate, sometimes rapidly and materially, in response to changes in the Underlying PIMCO Fund’s NAV, the value of the Underlying PIMCO Fund’s holdings and supply and demand for the Underlying PIMCO Fund’s shares. Although the creation/redemption feature of the Underlying PIMCO Funds generally makes it more likely that an Underlying PIMCO Fund’s shares will trade close to NAV, market volatility, lack of an active trading market for the Underlying PIMCO Fund’s shares, disruptions at market participants (such as authorized participants or market makers) and any disruptions in the ordinary functioning of the creation/redemption process may result in the Underlying PIMCO Fund’s shares trading significantly above (at a “premium”) or below (at a “discount”) NAV. An investor who buys or sells an Underlying PIMCO Fund’s shares may incur significant losses if the investor transacts in the Underlying PIMCO Fund’s shares in these and other circumstances. Neither PIMCO nor the Trust can predict whether an Underlying PIMCO Fund’s shares will trade above, below or at NAV. An Underlying PIMCO Fund’s investment results are based on the Underlying PIMCO Fund’s daily NAV. Investors transacting in an Underlying PIMCO Fund’s shares in the secondary market, where market prices may differ from NAV, may experience investment results that differ from results based on the Underlying PIMCO Fund’s daily NAV.
Municipal Project-Specific Risk
An Underlying PIMCO Fund may be more sensitive to adverse economic, business or political developments if it invests a substantial portion of its assets in the bonds of specific projects (such as those relating to education, health care, housing, transportation, and utilities), industrial development bonds, or in general obligation bonds, particularly if there is a large concentration from issuers in a single state.
Municipal Bond Risk
An Underlying PIMCO Fund that invests in Municipal Bonds may be affected significantly by the economic, regulatory or political developments affecting the ability of issuers of Municipal Bonds to pay interest or repay principal. In addition, the ability of an issuer to make payments or repay interest may be affected by litigation or bankruptcy. In the event of bankruptcy of such an issuer, an Underlying PIMCO Fund investing in the issuer’s securities could experience delays in collecting principal and interest, and the Underlying PIMCO Fund may not, in all circumstances, be able to collect all principal and interest to which it is entitled. To enforce its rights in the event of a default in the payment of interest or repayment of principal, or both, an Underlying PIMCO Fund may, in some instances, take possession of, and manage, the assets securing the issuer’s obligations on such securities, which may increase the Underlying PIMCO Fund’s operating expenses. Any income derived from the Underlying PIMCO Fund’s ownership or operation of such assets may not be tax-exempt. Municipal Bonds are subject to interest rate, credit and market risk.
Because many Municipal Bonds are issued to finance similar projects (such as those relating to education, health care, housing, transportation, and utilities), conditions in those sectors may affect the overall municipal securities market. In addition, changes in the financial condition of an individual municipal issuer can affect the overall municipal market. Municipal Bonds backed by current or anticipated revenues from a specific project or specific assets can be negatively affected by the discontinuance of the supporting taxation or the inability to collect revenues for the specific project or specific assets. Municipal Bonds are subject to the risk that the Internal Revenue Service (“IRS”) may determine that an issuer has not complied with applicable tax requirements and that interest from the Municipal Bond is taxable, which may result in a significant decline in the value of the security. Municipal Bonds may be less liquid than taxable bonds and there may be less publicly available information on the financial condition of Municipal Bond issuers than for issuers of other securities, and the investment performance of an Underlying PIMCO Fund investing in Municipal Bonds may therefore be more dependent on the analytical abilities of PIMCO than if the Underlying PIMCO Fund held other types of investments such as stocks or taxable bonds. The secondary market for Municipal Bonds also tends to be less well-developed or liquid than many other securities markets, a by-product of lower capital commitments to the asset class by the dealer community, which may adversely affect an Underlying PIMCO Fund’s ability to sell Municipal Bonds it holds at attractive prices or value Municipal Bonds.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in an Underlying PIMCO Fund’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Underlying PIMCO Fund is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and an Underlying PIMCO Fund may lose money as a result of movements in interest rates. An Underlying PIMCO Fund may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.

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Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When an Underlying PIMCO Fund holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Underlying PIMCO Fund’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Underlying PIMCO Fund may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Underlying PIMCO Fund is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Underlying PIMCO Fund. This is especially the case if the Underlying PIMCO Fund consists of securities with widely varying durations. Therefore, if the Underlying PIMCO Fund has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Underlying PIMCO Fund uses leverage or derivatives in connection with the management of the Underlying PIMCO Fund.
Convexity is an additional measure used to understand a security’s or an Underlying PIMCO Fund‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Underlying PIMCO Fund holds such securities, the Underlying PIMCO Fund may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
An Underlying PIMCO Fund could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/ or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by an Underlying PIMCO Fund may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Underlying PIMCO Fund. This is especially the case if the Underlying PIMCO Fund consists of securities with widely varying credit ratings. Therefore, if the Underlying PIMCO Fund has an average credit rating that suggests a certain credit quality, the Underlying PIMCO Fund may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Underlying PIMCO Fund uses leverage or derivatives in connection with the management of the Underlying PIMCO Fund. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/ or interest.

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High Yield Risk
Underlying PIMCO Funds that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Distressed Company Risk
An Underlying PIMCO Fund that invests in securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments. Issuers of distressed company securities may also be involved in restructurings or bankruptcy proceedings that may not be successful. An economic downturn or period of rising interest rates could adversely affect the market for these securities and reduce the Underlying PIMCO Fund’s ability to sell these securities (liquidity risk). If the issuer of a debt security is in default with respect to interest or principal payments, the Underlying PIMCO Fund may lose its entire investment.
Market Risk
The market price of securities owned by an Underlying PIMCO Fund may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors which affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by an Underlying PIMCO Fund. Even when markets perform well, there is no assurance that the investments held by an Underlying PIMCO Fund will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Underlying PIMCO Funds to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Underlying PIMCO Funds’ investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi- governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the

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ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent an Underlying PIMCO Fund from executing advantageous investment decisions in a timely manner. Underlying PIMCO Funds that have focused their investments in a region enduring geopolitical market disruption will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to an Underlying PIMCO Fund’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Underlying PIMCO Fund to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause an Underlying PIMCO Fund to lose enough value, the Underlying PIMCO Fund could also face increased shareholder redemptions, which could force the Underlying PIMCO Fund to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Underlying PIMCO Fund.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, an Underlying PIMCO Fund being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAVs, delays in NAV calculation and/or the inability to calculate NAVs over extended periods.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Underlying PIMCO Funds reasonably expect cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. An Underlying PIMCO Fund’s investments in illiquid investments may reduce the returns of the Underlying PIMCO Fund because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Underlying PIMCO Fund to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Underlying PIMCO Fund from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, an Underlying PIMCO Fund, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that an Underlying PIMCO Fund principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Underlying PIMCO Fund will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for an Underlying PIMCO Fund to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require an Underlying PIMCO Fund to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Underlying PIMCO Fund, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.

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Prospectus

Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Underlying PIMCO Funds may use are referenced under “Characteristics and Risks of Securities and Investment Techniques-Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. Underlying PIMCO Funds may also use derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. Underlying PIMCO Funds may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject an Underlying PIMCO Fund to the potential for unlimited loss. The use of derivatives may cause the Underlying PIMCO Fund’s investment returns to be impacted by the performance of securities the Underlying PIMCO Fund does not own and result in the Underlying PIMCO Fund’s total investment exposure exceeding the value of its portfolio.
An Underlying PIMCO Fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of the derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Underlying PIMCO Fund may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Underlying PIMCO Fund are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Underlying PIMCO Fund, or the derivatives or other strategies used by the Underlying PIMCO Fund, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Underlying PIMCO Fund invests. By investing in a derivative instrument, the Underlying PIMCO Fund could lose more than the initial amount invested, and derivatives may increase the volatility of the Underlying PIMCO Fund, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that an Underlying PIMCO Fund will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, an Underlying PIMCO Fund’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders.
Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Underlying PIMCO Fund’s clearing broker, or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which an Underlying PIMCO Fund may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If an Underlying PIMCO Fund incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Underlying PIMCO Fund might have been in a better position if the Underlying PIMCO Fund had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Underlying PIMCO Fund and its counterparty. Therefore, it may not be possible for an Underlying PIMCO Fund to modify, terminate, or offset the Underlying PIMCO Fund’s obligations or the Underlying PIMCO Fund’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Underlying PIMCO Fund. In such case, the Underlying PIMCO Fund may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, an Underlying PIMCO Fund may wish to retain the Underlying PIMCO Fund’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, an Underlying PIMCO Fund will be subject to increased liquidity and investment risk.

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When a derivative is used as a hedge against a position that an Underlying PIMCO Fund holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that an Underlying PIMCO Fund’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of an Underlying PIMCO Fund’s derivative transactions, impede the employment of the Underlying PIMCO Fund’s derivatives strategies, or adversely affect the Underlying PIMCO Fund’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Underlying PIMCO Funds' asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Underlying PIMCO Funds to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Underlying PIMCO Funds to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Underlying PIMCO Funds' ability to employ certain strategies that use these instruments and/or adversely affect the Underlying PIMCO Funds' performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Underlying PIMCO Funds' investments and cost of doing business, which could adversely affect investors.
Futures Contract Risk
A futures contract is an exchange-traded contract to buy or sell an underlying asset, such as a security, currency or commodity, for a set price on a future date. The risks associated with the Underlying PIMCO Fund’s use of derivative instruments, including futures contracts, are discussed in more detail under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and under “Investment Objectives and Policies” in the SAI. The purchase or sale of a futures contract may result in losses in excess of the amount invested in the futures contract. There can be no guarantee that there will be a correlation between price movements in the futures contract and the underlying asset. In addition, there are significant differences between the futures market and the markets for underlying assets, which could result in an imperfect correlation between the markets. The degree of imperfect correlation depends on circumstances such as variations in speculative market demand for futures and futures options on underlying assets, including technical influences in futures trading and futures options, and differences between the futures contract and underlying asset due to factors such as interest rate levels, maturities, and creditworthiness of issuers.
Futures contracts are traded on exchanges, so that, in most cases, a party can close out its position on the exchange for cash, without delivering the underlying asset. Because the futures utilized by certain Underlying PIMCO Funds are exchange-traded, the primary credit risk on futures contracts resides with the Underlying PIMCO Fund’s clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Underlying PIMCO Fund’s ability to invest in derivatives, limit an Underlying PIMCO Fund’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Underlying PIMCO Funds performance. Futures exchanges may limit the amount of fluctuation permitted in certain futures contract prices during a single trading day. There can be no assurance that a liquid market will exist at a time when an Underlying PIMCO Fund seeks to close out a futures or a futures option position, and that the Portfolio or Underlying PIMCO Fund would remain obligated to meet margin requirements until the position is closed.
In addition, certain futures contracts may be relatively new instruments without a significant trading history. As a result, there can be no assurance that an active secondary market will develop or continue to exist.
Model Risk
In making investment allocation decisions for a Portfolio or certain Underlying PIMCO Funds, as applicable, PIMCO or the Sub-Adviser, as applicable, may utilize quantitative models that may be proprietary or developed by third-parties. These models are used by PIMCO or the Sub-Adviser, as applicable, to determine (or assist in determining) the Portfolio’s or Underlying PIMCO Fund’s target asset allocation and to identify potentially attractive relative value and risk hedging strategies. The investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in a Portfolio or Underlying PIMCO Fund. There can be no assurance that the models used by PIMCO or the Sub-Adviser, as applicable, will remain viable, due to various factors, which may include the quality of the data input into the models and the assumptions underlying such models, which to varying degrees involve the exercise of judgment, as well as the possibility of errors in constructing or using the model. In addition, in constructing the underlying index of, or model portfolio for, an Underlying PIMCO Fund that seeks to track the investment results of such underlying index or model portfolio, the index provider or sub-adviser, as applicable, may utilize quantitative models or

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Prospectus

methodologies that may be proprietary or developed by third-parties. These models and methodologies are used to help determine the composition of the underlying index or model portfolio and may not adequately take into account certain factors, resulting in a decline in the value of the underlying index or model portfolio and, therefore, the Underlying PIMCO Fund.
Models rely on accurate market data inputs. If inaccurate market data is entered into a model, the resulting information will be incorrect. In addition, the models used may be predictive in nature and such models may result in an incorrect assessment of future events. The models evaluate securities or securities markets based on certain assumptions concerning the interplay of market factors. The markets or the prices of individual securities may be affected by factors not foreseen in developing the models. In addition, when relying on a quantitative model and/or data supplied by third parties, PIMCO or the Sub-Adviser may have less insight into the construction, coding or testing of the third-party model or data, and PIMCO and the Sub-Adviser will be exposed to systems, cyber security and other risks associated with the third party that provides the model or data.
The use of models can be complex and involves financial, economic, econometric and statistical theories, research and modeling; and the results of those processes must then be translated into computer code. Although PIMCO and the Sub-Adviser seek to hire individuals and/or third parties, as applicable, skilled in each of these functions and to provide appropriate levels of oversight, the complexity of the individual tasks, the difficulty of integrating such tasks, and the limited ability to perform “real world” testing of a model’s end product raises the chances that a finished model may contain an error; one or more of such errors could adversely affect a Portfolio’s or an Underlying PIMCO Fund’s performance.
Commodity Risk
An Underlying PIMCO Fund’s investments in commodity-linked derivative instruments may subject the Underlying PIMCO Fund to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments. Certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund® , may each concentrate its assets in a particular sector of the commodities market (such as oil, metal or agricultural products). As a result, to the extent the Portfolio invests in the PIMCO CommoditiesPLUS® Strategy Fund or PIMCO CommodityRealReturn Strategy Fund® , each an Underlying PIMCO Fund, the Portfolio may be more susceptible to risks associated with those sectors. The prices for commodities in those sectors may fluctuate widely due to factors such as changes in value, supply and demand and governmental regulatory policies.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if an Underlying PIMCO Fund holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing an Underlying PIMCO Fund to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an Underlying PIMCO Fund to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of an Underlying PIMCO Funds because the Underlying PIMCO Fund may have to reinvest that money at the lower prevailing interest rates. An Underlying PIMCO Fund’s investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

April 30, 2021 | PROSPECTUS  13

PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
Certain Underlying PIMCO Funds may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than portfolios that invest exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers.
Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Underlying PIMCO Fund’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Underlying PIMCO Fund could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that an Underlying PIMCO Fund invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Underlying PIMCO Fund will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Real Estate Risk
Underlying PIMCO Funds that invest in real estate investment trusts (“REITs”) or real estate-linked derivative instruments are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. An investment in a REIT or a real estate-linked derivative instrument that is linked to the value of a REIT is subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (the “Code”). In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. Finally, private REITs are not traded on a national securities exchange. As such, these products are generally illiquid. This reduces the ability of an Underlying PIMCO Fund to redeem its investment early. Private REITs are also generally harder to value and may bear higher fees than public REITs
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent an Underlying PIMCO Fund invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, technical, political and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent an Underlying PIMCO Fund invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Underlying PIMCO Fund may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. An Underlying PIMCO Fund that focuses its investments in multiple asset classes of emerging marketsecurities may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. An Underlying PIMCO Fund may also be subject to Emerging Markets Risk if they invest in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Underlying PIMCO Funds could lose money the economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers of such emerging markets may be more affected by the performance of such industries or sectors..

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If an Underlying PIMCO Fund invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, an Underlying PIMCO Fund’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that an Underlying PIMCO Fund invests in foreign (non-U.S.)currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Issuer Non-Diversification Risk
Focusing investments in a small number of issuers increases risk. Underlying PIMCO Funds that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than Underlying PIMCO Funds that are “diversified.” Underlying PIMCO Funds that invest in a relatively small number of issuers are more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Some of those issuers also may present substantial credit or other risks.
To the extent that the Portfolio invests a significant portion of its assets in an Underlying PIMCO Fund, the Portfolio will be particularly sensitive to the risks associated with that Underlying PIMCO Fund. For a discussion of risks associated with Underlying PIMCO Funds, please see “Fund of Funds Risk” above.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate its leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. Underlying PIMCO Funds also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause an Underlying PIMCO Fund to liquidate portfolio positions to satisfy its obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause an Underlying PIMCO Fund to be more volatile than if the Underlying PIMCO Fund had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Underlying PIMCO Fund’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Underlying PIMCO Fund does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where an Underlying PIMCO Fund, for any reason, is unable to close out the transaction. In addition, to the extent an Underlying PIMCO Fund borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed an Underlying PIMCO Fund’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, an Underlying PIMCO Fund may be forced to sell portfolio securities when it is not otherwise advantageous to do so.

April 30, 2021 | PROSPECTUS  15

PIMCO Variable Insurance Trust

Smaller Company Risk
The general risks associated with fixed income securities and equity securities are particularly pronounced for securities issued by companies with smaller market capitalizations. These companies may have limited product lines, markets or financial resources or they may depend on a few key employees. As a result, they may be subject to greater levels of credit, market and issuer risk. Securities of smaller companies may trade less frequently and in lesser volumes than more widely held securities and their values may fluctuate more sharply than other securities. Companies with medium-sized market capitalizations may have risks similar to those of smaller companies.
Management Risk
Certain Underlying PIMCO Funds are subject to management risk because they are actively managed investment portfolios. PIMCO or the Sub-Adviser, as applicable, and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Underlying PIMCO Funds, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which an Underlying PIMCO Fund seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Underlying PIMCO Fund. To the extent the Underlying PIMCO Fund employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Underlying PIMCO Fund. Certain Underlying PIMCO Funds are also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Underlying PIMCO Fund or hinder Underlying PIMCO Fund operations. For example, trading delays or errors (both human and systematic) could prevent an Underlying PIMCO Fund from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Underlying PIMCO Funds and may also adversely affect the ability of the Underlying PIMCO Funds to achieve their investment objectives. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on an Underlying PIMCO Fund’s ability to realize its investment objective.
Because a number of Underlying PIMCO Funds obtain exposure to certain proprietary model stock portfolios by investing in equity total return swaps based on such model portfolios, in other securities and instruments to replicate the performance of such model portfolios, or directly in the equity securities held in such model portfolios, such Underlying PIMCO Funds will be subject to the risks associated with the management of these proprietary model stock portfolios by the sub-adviser to such Underlying PIMCO Funds. Similarly, there can be no assurance that quantitative models or methods utilized by PIMCO or the Sub-Adviser or related data sources will always be available, and the loss of access to any such model(s) or data sources could have an adverse impact on the Underlying PIMCO Fund's ability to realize its investment objective.
Short Exposure Risk
An Underlying PIMCO Fund’s short sales, if any, are subject to special risks. A short sale involves the sale by the Underlying PIMCO Fund of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. An Underlying PIMCO Fund may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Underlying PIMCO Fund will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, an Underlying PIMCO Fund could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase an Underlying PIMCO Fund’s exposure to long security positions and make any change in the Underlying PIMCO Fund’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy an Underlying PIMCO Fund employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, an Underlying PIMCO Fund may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Underlying PIMCO Fund.

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Risk
The PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund in which the Portfolio may invest, gain exposure to the commodities markets through investments in commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures. The PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund may also gain exposure indirectly to commodity markets by investing in their respective subsidiaries (the “Subsidiaries”), which invest primarily in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and/or other Fixed Income Instruments. In order for each Underlying PIMCO Fund to qualify as a regulated investment company under Subchapter M of the Code, the Underlying PIMCO Fund must derive at least 90 percent of its gross income each taxable year from certain qualifying sources of income.
As more fully described below under “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” the IRS issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. The IRS has issued private letter rulings in which the IRS specifically concluded that income derived from the Underlying PIMCO Fund’s investment in its Subsidiary will also constitute qualifying income to each Underlying PIMCO Fund. Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if an Underlying PIMCO Fund‘s income from an investment in the subsidiary is distributed annually or is derived with respect to the Underlying PIMCO Fund’s business of investing in securities. An IRS revenue procedure states that the IRS will issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the Investment Company Act of 1940, as amended (the “1940 Act”).
Each Underlying PIMCO Fund will seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in its respective Subsidiary. If the IRS were to determine that income derived from certain commodity-linked notes or from investments in the Subsidiary does not constitute qualifying income, the Portfolio and certain Underlying PIMCO Funds, including the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund, might be adversely affected and would be required to reduce their exposure to such investments which might result in difficulty in implementing their investment strategies and increased costs and taxes. The use of commodity index-linked notes and investments in the Subsidiaries involve specific risks. See “Characteristics and Risks of Securities and Investment Techniques-Derivatives-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” below for further information regarding commodity index-linked notes, including the risks associated with these instruments. In addition, see “Characteristics and Risks of Securities and Investment Techniques-Investments in a Wholly-Owned Subsidiary” below for further information regarding the Subsidiaries, including the risks associated with investing in the Subsidiaries.
To the extent the Portfolio invests in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund®, or PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, the use of the above noted investments by the Underlying PIMCO Fund could subject the shareholders of the Portfolio to risks similar to those borne by shareholders of the PIMCO CommodityRealReturn® Strategy and PIMCO Global Managed Asset Allocation Portfolios. See “Tax Consequences.”
Subsidiary Risk
By investing in their respective Subsidiaries, the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund, Underlying PIMCO Funds, are indirectly exposed to the risks associated with the respective Subsidiary’s investments. The investments held by the Subsidiaries are generally similar to those that are permitted to be held by these Underlying PIMCO Funds and are subject to the same risks that apply to similar investments if held directly by the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund or PIMCO TRENDS Managed Futures Strategy Fund. These risks are described elsewhere in this prospectus. There can be no assurance that the investment objectives of the Underlying PIMCO Funds or the Subsidiaries will be achieved.
The Subsidiaries are not registered under the 1940 Act, and, unless otherwise noted in this prospectus, are not subject to all the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund and/or the Subsidiaries to operate as described in this prospectus and the SAI and could adversely affect the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund and, to the extent the Portfolio invests in the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund, the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of an Underlying PIMCO Fund and/or a Subsidiary and result in the Underlying PIMCO Fund underperforming its benchmark index(es).

April 30, 2021 | PROSPECTUS  17

PIMCO Variable Insurance Trust

Value Investing Risk
Value investing attempts to identify companies that are believed to be undervalued. Value stocks typically have prices that are low relative to factors such as the company’s earnings, cash flow or dividends. A value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur. A value investing style may perform better or worse than equity portfolios that focus on growth stocks or that have a broader investment style.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.
Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
Exchange-Traded Fund (“ETF”) Risk
Investments in ETFs entail certain risks. Investments in ETFs designed to track an index involve the risk that the ETF’s performance may not track the performance of the index the ETF is designed to track. This deviation may occur due to cash inflows and outflows from and to investors buying and redeeming shares or due to occasional differences between the composition of the index and the securities held by the ETF. In addition, investments in ETFs involve the risk that the market prices of ETF shares will fluctuate, sometimes rapidly and materially, in response to changes in the ETF’s NAV, the value of ETF holdings and supply and demand for ETF shares. Although ETFs will generally trade close to NAV, market volatility, lack of an active trading market for ETF shares, disruptions at market participants (such as Authorized Participants or market makers) and any disruptions in the ordinary functioning of the creation/redemption process may result in ETF shares trading significantly above (at a “premium”) or below (at a “discount”) NAV. Significant losses may result when transacting in ETF shares in these and other circumstances.
Tracking Error Risk
An Underlying PIMCO Fund that seeks to track the investment results of an index may not invest in every component security of its underlying index. Imperfect correlation between an Underlying PIMCO Fund’s portfolio and its underlying index, asset valuation, timing variances, changes to the underlying index and regulatory requirements may cause the Underlying PIMCO Fund’s performance to diverge from the performance of its underlying index. Tracking error may also result because an Underlying PIMCO Fund incurs fees and expenses while its underlying index does not incur such fees and expenses. Such expenses include the costs of buying and selling securities, such as when an Underlying PIMCO Fund rebalances its portfolio to reflect changes in the composition of the underlying index. These expenses may be higher for an Underlying PIMCO Fund investing in foreign (non-U.S.) securities. The performance of an Underlying PIMCO Fund and the underlying index may vary due to differences between the Underlying PIMCO Fund’s portfolio and the underlying index due to legal restrictions, cost or liquidity restraints. The risk that performance of an Underlying PIMCO Fund and the underlying index may vary may be heightened during periods of market volatility or other unusual market conditions. Because an underlying index is not subject to the tax diversification requirements to which an Underlying PIMCO Fund must adhere, the Underlying PIMCO Fund may be required to deviate its investments from the securities and relative weightings of its underlying index. For tax efficiency purposes, an Underlying PIMCO Fund may sell certain securities to realize losses, which will result in a deviation from its underlying index. An Underlying PIMCO Fund may not be fully invested at times either as a result of cash flows into the Fund or reserves of cash held by the Fund to meet redemptions and to

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

pay expenses. In addition, if an Underlying PIMCO Fund uses a representative sampling approach, this approach may cause the Underlying PIMCO Fund to be less correlated with the return of the underlying index than if the Underlying PIMCO Fund held all of the securities in the underlying index with the same relative weightings as the underlying index.
Indexing Risk
Certain Underlying PIMCO Funds use an indexing approach and may be affected by a general decline in market segments or asset classes relating to their underlying indexes. Those Underlying PIMCO Funds invest in securities and instruments included in, or representative of, their underlying indexes regardless of the investment merits of the underlying indexes. Additionally, errors in the construction or calculation of an Underlying PIMCO Fund’s underlying index may occur from time to time, and the index provider may not identify or correct such errors for some period of time. Any such underlying index construction or calculation error may adversely impact the Underlying PIMCO Fund.
LIBOR Transition Risk
Certain instruments in which an Underlying PIMCO Fund may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on an Underlying PIMCO Fund or on certain instruments in which an Underlying PIMCO Fund invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of an Underlying PIMCO Fund's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by an Underlying PIMCO Fund or a reduction in the effectiveness of related Underlying PIMCO Fund transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of an Underlying PIMCO Fund that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to an Underlying PIMCO Fund.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

April 30, 2021 | PROSPECTUS  19

PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
PIMCO has engaged Research Affiliates, a California limited liability company (“Research Affiliates”), to serve as the asset allocation sub-adviser to the PIMCO All Asset Portfolio. Research Affiliates was organized in 2002 and is located at 620 Newport Center Drive, Suite 900, Newport Beach, CA 92660. As asset allocation sub-adviser for this Portfolio, Research Affiliates is responsible for recommending how the assets of the Portfolio are allocated and reallocated from time to time among the Underlying PIMCO Funds.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.425% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.175% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract and asset allocation sub-advisory agreement is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) . PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.

20  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Fund of Funds Fees
The Portfolio is permitted to invest in Underlying PIMCO Funds, which, for the Portfolio, is defined to include the least expensive class of shares of any actively managed or smart beta funds (including mutual funds or exchange-traded funds) of PIMCO Funds, PIMCO ETF Trust or PIMCO Equity Series, each an affiliated open-end investment company, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. Shares of the PIMCO All Asset: Multi-Real Fund, PIMCO All Asset: Multi-RAE PLUS Fund and PIMCO All Asset: Multi-Short PLUS Fund (the “PAPS All Asset Funds”) may be purchased only by the Portfolio, as well as by the PIMCO All Asset Fund and PIMCO All Asset All Authority Fund, each a series of PIMCO Funds, an affiliated investment company. 
The Portfolio pays advisory fees directly to PIMCO at an annual rate of 0.175% based on the average daily net assets attributable in the aggregate to the Portfolio’s Advisor Class shares. The Portfolio pays supervisory and administrative fees directly to PIMCO at an annual rate of 0.25% based on the average daily net assets attributable in the aggregate to the Portfolio’s Advisor Class shares. The Portfolio also indirectly pays its proportionate share of the advisory, supervisory and administrative and management fees charged by PIMCO to the Underlying PIMCO Funds and, to the extent not included among the Underlying PIMCO Funds, funds of PIMCO ETF Trust in which the Portfolio invests (collectively, “Underlying PIMCO Fund Fees”).
PIMCO has contractually agreed, through May 1, 2022, to waive the Portfolio’s advisory fee to the extent that the Underlying PIMCO Fund Fees exceed 0.64% of the total assets invested in Underlying PIMCO Funds. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the advisory fee waived as set forth above (the “Asset Allocation Reimbursement Amount”) during the previous thirty-six months from the time of waiver, provided that such amount paid to PIMCO will not: 1) together with any Underlying PIMCO Fund Fees exceed, for such month, the applicable expense limit; 2) exceed the total Asset Allocation Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
The Acquired Fund Fees and Expenses shown in the Annual Portfolio Operating Expenses table for the Portfolio may be higher than the Underlying PIMCO Fund Fees used for purposes of the Expense Reduction shown in that table due to differences in the methods of calculation. The Acquired Fund Fees and Expenses, as required to be shown in the Annual Portfolio Operating Expenses table, are calculated using the total operating expenses for each Underlying PIMCO Fund over the Portfolio’s average net assets. The Underlying PIMCO Fund Fees that are used for purposes of implementing the expense reduction described above are calculated using the advisory and supervisory and administrative fees for each Underlying PIMCO Fund over the total assets invested in Underlying PIMCO Funds. Thus, the Acquired Fund Fees and Expenses listed in the Annual Portfolio Operating Expenses table will typically be higher than the Underlying PIMCO Fund Fees used to calculate the Expense Reduction when the Portfolio employs leverage as an investment strategy.
The expenses associated with investing in a fund of funds are generally higher than those for mutual funds that do not invest in other funds. The cost of investing in the Portfolio will generally be higher than the cost of investing in a portfolio that invests directly in individual stocks and bonds. By investing in the Portfolio, an investor may indirectly bear a portion of the fees and expenses charged by Underlying PIMCO Funds, to the extent such fees and expenses are not waived or reimbursed pursuant to applicable waiver and reimbursement agreements, in addition to the Portfolio’s direct fees and expenses. In addition, the use of a fund of funds structure could affect the timing, amount and character of distributions to shareholders and may therefore increase the amount of taxes payable by shareholders. The Portfolio invests in the least expensive class of shares of the Underlying PIMCO Funds, which are not subject to any sales charges or distribution (12b-1) fees.
The following table summarizes the annual expenses borne by Institutional Class or Class M shareholders of the Underlying PIMCO Funds (or, in the case of the PAPS All Asset Funds and those operating as exchange-traded funds, the Underlying PIMCO Fund shareholders). Because the Portfolio invests in the least expensive class of shares of the Underlying PIMCO Funds, shareholders of the Portfolio would indirectly bear a proportionate share of these expenses, depending upon how the Portfolio’s assets are allocated from time to time among the Underlying PIMCO Funds.
For a complete description of an Underlying PIMCO Fund, please see the Underlying PIMCO Fund’s Institutional Class or Class M prospectus or offering memorandum, as applicable. For a summary description of the Underlying PIMCO Funds, please see the “Descriptions of the Underlying PIMCO Funds” section in this prospectus.
Annual Underlying PIMCO Fund Expenses
(Based on the average daily net assets attributable to an Underlying PIMCO Fund’s Institutional Class shares (or Class M shares in the case of the PIMCO Government Money Market Fund , or the Fund in the case of the PAPS All Asset Funds and exchange-traded funds of the PIMCO ETF Trust or PIMCO Equity Series)).)).
Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO Active Bond Exchange-Traded Fund
0.55%
0.02%
0.57%
PIMCO All Asset: Multi-RAE PLUS Fund
0.89%
0.00%
0.89%
PIMCO All Asset: Multi-Real Fund
0.74%
0.12%
0.86%(3)

April 30, 2021 | PROSPECTUS  21

PIMCO Variable Insurance Trust

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO All Asset: Multi-Short PLUS Fund
0.74%
0.02%
0.76%(3)
PIMCO California Intermediate Municipal Bond Fund
0.445%
0.00%
0.445%
PIMCO California Municipal Bond Fund
0.44%
0.02%
0.46%
PIMCO California Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Climate Bond Fund
0.50%
0.00%
0.50%
PIMCO CommoditiesPLUS® Strategy Fund
0.74%
0.27%
1.01%(4)
PIMCO CommodityRealReturn Strategy Fund®
0.74%
0.76%
1.50%(5)
PIMCO Credit Opportunities Bond Fund
0.90%
0.02%
0.92%
PIMCO Diversified Income Fund
0.75%
0.04%
0.79%
PIMCO Dividend and Income Fund
0.75%
0.05%
0.80%(6)
PIMCO Dynamic Bond Fund
0.80%
0.05%
0.85%
PIMCO Emerging Markets Bond Fund
0.83%
0.05%
0.88%
PIMCO Emerging Markets Corporate Bond Fund
0.90%
0.12%
1.02%
PIMCO Emerging Markets Currency and Short-Term Investments Fund
0.85%
0.03%
0.88%
PIMCO Emerging Markets Local Currency and Bond Fund
0.90%
0.80%
1.70%
PIMCO Enhanced Low Duration Active Exchange-Traded Fund
0.46%
0.10%
0.56%
PIMCO Enhanced Short Maturity Active ESG Exchange-Traded Fund
0.36%
0.03%
0.39%(7)
PIMCO Enhanced Short Maturity Active Exchange-Traded Fund
0.35%
0.02%
0.37%
PIMCO ESG Income Fund
0.50%
0.07%
0.57%(8)
PIMCO Extended Duration Fund
0.50%
1.21%
1.71%
PIMCO Global Advantage® Strategy Bond Fund
0.65%
0.21%
0.86%
PIMCO Global Bond Opportunities Fund (U.S. Dollar-Hedged)
0.55%
0.04%
0.59%
PIMCO Global Bond Opportunities Fund (Unhedged)
0.55%
0.12%
0.67%
PIMCO GNMA and Government Securities Fund
0.50%
0.33%
0.83%
PIMCO Government Money Market Fund
0.18%
0.00%
0.18%(9)
PIMCO High Yield Fund
0.55%
0.02%
0.57%
PIMCO High Yield Municipal Bond Fund
0.55%
0.08%
0.63%
PIMCO High Yield Spectrum Fund
0.60%
0.02%
0.62%
PIMCO Income Fund
0.50%
0.59%
1.09%
PIMCO Intermediate Municipal Bond Active Exchange-Traded Fund
0.35%
0.00%
0.35%
PIMCO International Bond Fund (U.S. Dollar-Hedged)
0.50%
0.10%
0.60%
PIMCO International Bond Fund (Unhedged)
0.50%
0.13%
0.63%
PIMCO Investment Grade Credit Bond Fund
0.50%
0.35%
0.85%
PIMCO Long Duration Total Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term Credit Bond Fund
0.55%
0.29%
0.84%
PIMCO Long-Term Real Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term U.S. Government Fund
0.475%
1.38%
1.855%
PIMCO Low Duration Credit Fund(10)
0.70%
0.05%
0.75%
PIMCO Low Duration ESG Fund
0.50%
0.08%
0.58%
PIMCO Low Duration Fund
0.46%
0.41%
0.87%
PIMCO Low Duration Fund II
0.50%
0.03%
0.53%
PIMCO Low Duration Income Fund
0.50%
0.05%
0.55%
PIMCO Moderate Duration Fund
0.46%
0.15%
0.61%
PIMCO Mortgage Opportunities and Bond Fund
0.60%
1.22%
1.82%
PIMCO Mortgage-Backed Securities Fund
0.50%
0.25%
0.75%
PIMCO Municipal Bond Fund
0.44%
0.07%
0.51%
PIMCO National Intermediate Municipal Bond Fund
0.45%
0.00%
0.45%
PIMCO New York Municipal Bond Fund
0.445%
0.05%
0.495%
PIMCO Preferred and Capital Securities Fund
0.79%
0.09%
0.88%(11)
PIMCO RAE Emerging Markets Fund
0.75%
0.02%
0.77%(6)
PIMCO RAE Fundamental Advantage PLUS Fund
0.89%
0.07%
0.96%
PIMCO RAE International Fund
0.50%
0.02%
0.52%(6)

22  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO RAE PLUS EMG Fund
1.10%
0.21%
1.31%
PIMCO RAE PLUS Fund
0.79%
0.08%
0.87%
PIMCO RAE PLUS International Fund
0.82%
0.05%
0.87%
PIMCO RAE PLUS Small Fund
0.84%
0.09%
0.93%
PIMCO RAE US Fund
0.40%
0.02%
0.42%(6)
PIMCO RAE US Small Fund
0.50%
0.04%
0.54%
PIMCO RAE Worldwide Long/Short PLUS Fund
1.19%
0.09%
1.28%
PIMCO RAFI Dynamic Multi-Factor Emerging Markets Equity ETF
0.49%
0.01%
0.50%(12)
PIMCO RAFI Dynamic Multi-Factor International Equity ETF
0.39%
0.02%
0.41%(12)
PIMCO RAFI Dynamic Multi-Factor U.S. Equity ETF
0.29%
0.02%
0.31%(12)
PIMCO RAFI ESG U.S. ETF
0.29%
0.01%
0.30%
PIMCO Real Return Fund
0.45%
0.08%
0.53%
PIMCO RealEstateRealReturn Strategy Fund
0.74%
1.36%
2.10%
PIMCO Short Asset Investment Fund
0.34%
0.02%
0.36%
PIMCO Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Short Term Municipal Bond Active Exchange-Traded Fund
0.35%
0.00%
0.35%
PIMCO Short-Term Fund
0.45%
0.10%
0.55%
PIMCO StocksPLUS® Absolute Return Fund
0.64%
0.08%
0.72%
PIMCO StocksPLUS® Fund
0.50%
0.06%
0.56%
PIMCO StocksPLUS® International Fund (U.S. Dollar-Hedged)
0.75%
0.25%
1.00%
PIMCO StocksPLUS® International Fund (Unhedged)
0.64%
0.38%
1.02%
PIMCO StocksPLUS® Long Duration Fund
0.59%
0.42%
1.01%
PIMCO StocksPLUS® Short Fund
0.64%
0.45%
1.09%
PIMCO StocksPLUS® Small Fund
0.69%
0.06%
0.75%
PIMCO Strategic Bond Fund
0.55%
0.02%
0.57%(13)
PIMCO Total Return ESG Fund
0.50%
0.46%
0.96%
PIMCO Total Return Fund
0.46%
0.24%
0.70%
PIMCO Total Return Fund II
0.50%
0.26%
0.76%
PIMCO Total Return Fund IV
0.50%
0.30%
0.80%
PIMCO TRENDS Managed Futures Strategy Fund
1.40%
0.29%
1.69%(14)
1
“Management Fees” reflects an advisory fee and a supervisory and administrative fee payable by an Underlying PIMCO Fund to PIMCO.
2
Other Expenses include expenses such as organizational expenses, interest expense, taxes, governmental fees, pro rata Trustees' fees and acquired fund fees and expenses attributable to the Institutional Class or Class M shares or the Fund in the case of exchange-traded funds of the PIMCO ETF Trust or PIMCO Equity Series.
3
PIMCO has contractually agreed, through July 31, 2021, to waive a portion of the Fund’s supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Funds at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided certain conditions are met.
4
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund III Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
5
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund I Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
6
PIMCO has contractually agreed, through October 31, 2021, to waive a portion of the Fund's supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund's organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Equity Series at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
7
PIMCO has contractually agreed, through October 31, 2022, to reduce its management fee by 0.12% of the average daily net assets of the Fund. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO ETF Trust at least 30 days prior to the end of the then current term. In any month in which the investment

April 30, 2021 | PROSPECTUS  23

PIMCO Variable Insurance Trust

management agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the management fee waived as set forth above during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
8
PIMCO has contractually agreed, through July 31, 2022, to waive a portion of the Fund’s supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
9
To maintain certain net yields for the Fund, PIMCO or its affiliates may temporarily and voluntarily waive, reduce or reimburse all or any portion of the Fund's fees and expenses.
10
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund.
11
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Capital Securities Fund (Cayman) Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
12
PIMCO has contractually agreed, through October 31, 2021, to waive a portion of the Fund’s management fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Equity Series at least 30 days prior to the end of the then current term. In any month in which the investment management agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the management fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
13
PIMCO has contractually agreed, through July 31, 2021, to reduce its supervisory and administrative fee for each share class of the Fund by 0.05% of the average daily net assets attributable to the applicable class of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years from the date of waiver.
14
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund VIII, Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO All Asset
Robert D. Arnott
4/03*
Chairman and Founder, Research Affiliates, since July 2002. Previously, Mr. Arnott was
Chairman of First Quadrant, L.P. until April 2004. He first joined First Quadrant in April
1998.
PIMCO All Asset
Christopher J. Brightman
11/16
Chief Investment Officer, Research Affiliates, since April 2014. Previously at Research
Affiliates, Mr. Brightman served as a Managing Director and Head of Investment
Management. Prior to joining Research Affiliates in 2010, Mr. Brightman was chief
executive officer of the University of Virginia Investment Management Company.
*
Inception of the Portfolio.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.

24  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

April 30, 2021 | PROSPECTUS  25

PIMCO Variable Insurance Trust

Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

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From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Underlying PIMCO Funds’ investment strategies may expose such Underlying PIMCO Funds to risks associated with market timing activities. For example, since some Underlying PIMCO Funds may invest in non-U.S. securities, they may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of an Underlying PIMCO Fund’s non-U.S. portfolio securities and the determination of the Underlying PIMCO Fund’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling fund shares at a price that does not reflect their true value. A similar risk exists for an Underlying PIMCO Fund’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
Except as identified below, to discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders (“Market Timing Policy”). Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders. In addition, purchases and sales by the Portfolio in certain Underlying PIMCO Funds may be exempt from certain limitations under the Market Timing Policy in order to allow the Portfolio to manage its cash flows and reallocate portfolio investments in the Underlying PIMCO Funds according to its allocation targets.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or

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refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio and Underlying PIMCO Fund shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or an Underlying PIMCO Fund or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
The assets of the Portfolio consist of shares of the Underlying PIMCO Funds, which are valued at their respective NAVs at the time of valuation of the Portfolio’s shares. For purposes of calculating the NAV of the Underlying PIMCO Funds, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services,
quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of an Underlying PIMCO Fund’s assets that are invested in one or more open-end management investment companies, (other than exchange-traded funds), the Underlying PIMCO Fund’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity

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securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of an Underlying PIMCO Fund’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio invests in Underlying PIMCO Funds that hold foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Trustees or persons acting at their direction. The Trustees has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO.
Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of an Underlying PIMCO Fund’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of
the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When an Underlying PIMCO Fund uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board of Trustees or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s and Underlying PIMCO Funds’ NAVs that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Underlying PIMCO Fund could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by an Underlying PIMCO Fund may differ from the value that would be realized if the securities were sold. An Underlying PIMCO Fund’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.

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Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.The Portfolio may invest in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund. One of the requirements for favorable tax treatment as a regulated investment company under the Code is that each Underlying PIMCO Fund derive at least 90% of its gross income from certain qualifying sources of income. The IRS has issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. As such, each Underlying PIMCO Fund’s ability to utilize commodity-linked swaps as part of its investment strategy is limited to a maximum of 10 percent of its gross income.
However, in a subsequent revenue ruling, the IRS provides that income from alternative investment instruments (such as certain commodity index-linked notes) that create commodity exposure may be considered qualifying income under the Code. The IRS has also issued a private letter ruling to the Underlying PIMCO Funds in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued another private letter ruling to each Underlying PIMCO Fund in which the IRS specifically concluded that income derived from the Underlying PIMCO Fund’s investment in its Subsidiary will also constitute qualifying income to the Underlying PIMCO Fund, even if the Subsidiary itself owns commodity linked swaps. Each Underlying PIMCO Fund will continue to seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in its Subsidiary.
Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if an Underlying PIMCO Fund‘s income from an investment in the subsidiary is derived with respect to the Underlying PIMCO Fund’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the 1940 Act. In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings. There can be no assurance that the IRS will not change its position with respect to some or all of these conclusions or that future legislation will not adversely impact the tax treatment of each Underlying PIMCO Fund’s commodity-linked investments. If the IRS were to change or reverse its position, or if future legislation adversely affected the tax treatment of the commodity-linked investments of each Underlying PIMCO Fund, there would likely be a significant adverse impact on the Underlying
PIMCO Fund, including the possibility of failing to qualify as a regulated investment company. If an Underlying PIMCO Fund did not qualify as a regulated investment company for any taxable year, its taxable income would be subject to tax at the Underlying PIMCO Fund level at regular corporate tax rates (without reduction for distributions to shareholders) and to a further tax at the shareholder level when such income is distributed.
Furthermore, the tax treatment of commodity-linked notes, other commodity-linked derivatives, and an Underlying PIMCO Fund’s investments in its Subsidiary may otherwise be adversely affected by future legislation, court decisions, Treasury Regulations and/or guidance issued by the IRS. Such developments could affect the character, timing and/or amount of the Underlying PIMCO Fund’s taxable income or any distributions made by the Underlying PIMCO Fund or result in the inability of the Underlying PIMCO Fund to operate as described in its prospectus.
A Note on the PIMCO CommodityRealReturn Strategy Fund®, an Underlying PIMCO Fund.Periodic adjustments for inflation to the principal amount of an inflation-indexed bond may give rise to original issue discount, which will be includable in the Underlying PIMCO Fund’s gross income. Due to original issue discount, the Underlying PIMCO Fund may be required to make annual distributions to shareholders that exceed the cash received, which may cause the Underlying PIMCO Fund to liquidate certain investments when it is not advantageous to do so. Also, if the principal value of an inflation-indexed bond is adjusted downward due to deflation, amounts previously distributed in the taxable year may be characterized in some circumstances as a return of capital.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
The Portfolio invests substantially all of its assets in shares of the Underlying PIMCO Funds, and as such (unless otherwise noted) does not invest directly in the securities described below. The Underlying PIMCO Funds, however, may invest in such securities. Because the value of an investment in the Portfolio is directly related to the investment performance of the Underlying PIMCO Funds in which it invests, the risks of investing in the Portfolio are closely related to the risks associated with the Underlying PIMCO Funds and their investments in the securities described below. Please see the “Descriptions of the Underlying PIMCO Funds.”
This section provides additional information about some of the principal investments and related risks of the Portfolio and the Underlying PIMCO Funds described under the “Portfolio Summary,” “Description of Principal Risks” and “Descriptions of the Underlying PIMCO Funds.” It

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also describes characteristics and risks of additional securities and investment techniques that may be used by the Underlying PIMCO Funds from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Underlying PIMCO Funds. As with any mutual fund, investors in the Underlying PIMCO Funds rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Underlying PIMCO Funds.
Because the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, may each invest a portion of its assets in its respective Subsidiary, each of which may hold some of the investments described in this prospectus, each Underlying PIMCO Fund, and to the extent the Portfolio invests in each Underlying PIMCO Fund, the Portfolio, may be indirectly exposed to the risks associated with those investments. With respect to its investments, each Subsidiary will generally be subject to the same fundamental, non-fundamental and certain other investment restrictions as the respective Underlying PIMCO Fund; however, each Subsidiary (unlike the Underlying PIMCO Fund) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. Each Underlying PIMCO Fund and each Subsidiary may test for compliance with certain investment restrictions on a consolidated basis, except that with respect to its investments in certain securities that may involve leverage, the Subsidiary will comply with asset segregation or “earmarking” requirements to the same extent as its respective Underlying PIMCO Fund.
Investors should be aware that the investments made by a Portfolio and the results achieved by a Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to a Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact a Portfolio’s portfolio management. For example, a Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause Portfolios to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase a Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause a Portfolio to perform differently than intended.
Similarly, significant shareholder purchases may adversely affect a Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
Most of the Underlying PIMCO Funds seek maximum total return. The total return sought by an Underlying PIMCO Fund consists of both income earned on the Underlying PIMCO Fund’s investments and capital appreciation, if any, arising from increases in the market value of the Underlying PIMCO Fund’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation or improving credit fundamentals for a particular market sector or security.
In selecting securities for an Underlying PIMCO Fund, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Underlying PIMCO Fund’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income

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Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example,
the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate

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collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Underlying PIMCO Fund to sell its bonds at attractive pries or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolios may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Underlying PIMCO Funds may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Underlying PIMCO Funds may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Underlying PIMCO Funds is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account
securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Underlying PIMCO Funds may subject the Underlying PIMCO Funds to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if an Underlying PIMCO Fund sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
Certain Underlying PIMCO Funds may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that an Underlying PIMCO Fund investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.

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Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose an Underlying PIMCO Fund to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The value of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk.Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect an Underlying PIMCO Fund’s returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Underlying PIMCO Funds may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk.Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Underlying PIMCO Funds to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of
principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on an Underlying PIMCO Fund’s yield to maturity from these securities. Certain Underlying PIMCO Funds may invest up to 5% of their total assets in any combination of mortgage-related or other asset backed IO, PO or inverse floater securities.
An Underlying PIMCO Fund may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties.
Loan Participations and Assignments
Certain Underlying PIMCO Funds may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If an Underlying PIMCO Fund purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
An Underlying PIMCO Fund may be subject to the risk that the returns of the Underlying PIMCO Fund will decline during periods of falling interest rates because the Underlying PIMCO Fund may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Underlying PIMCO Fund’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Underlying PIMCO Fund to invest in lower-yielding securities. An Underlying PIMCO Fund also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Underlying PIMCO Fund’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by an Underlying PIMCO Fund from its investments is likely to have an adverse effect on the Underlying PIMCO Fund’s NAV, yield and total return.

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Focused Investment
To the extent that an Underlying PIMCO Fund focuses its investments in a particular sector, the Underlying PIMCO Fund may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, an Underlying PIMCO Fund may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Underlying PIMCO Fund to greater risk. An Underlying PIMCO Fund also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. Certain Underlying PIMCO Funds may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case an Underlying
PIMCO Fund may lose its entire investment. The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which an Underlying PIMCO Fund may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. Each Underlying PIMCO Fund may invest in floating rate debt instruments (“floaters”) and certain Underlying PIMCO Funds may engage in credit spread trades. . A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Certain Underlying PIMCO Funds may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. Underlying PIMCO Funds that may invest in these securities may invest up to 5% of their total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, certain Underlying PIMCO Funds may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in

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the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Volatility
Volatility measures the variability in the price of an investment over time. A higher volatility level signifies an investment’s value may fluctuate over a larger range within a short period of time, either up or down. A lower volatility level means an investment’s value is more likely to change within a narrower range, or less frequently, over time. The more volatile the portfolio holdings of the Portfolio, the less predictable the returns for the Portfolio. Higher volatility levels may indicate heightened risk of losses.
PIMCO’s use of investments in seeking to manage the Portfolio‘s volatility will be consistent with the Portfolio’s asset allocation guidelines. Although asset allocation cannot eliminate investment risk or losses, it may provide opportunities to manage a Portfolio’s volatility relative to a Portfolio’s target annualized volatility level.
Event-Linked Exposure
Certain Underlying PIMCO Funds may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to
defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, an Underlying PIMCO Fund may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposures may also expose an Underlying PIMCO Fund to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposures may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
Certain Underlying PIMCO Funds may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. An Underlying PIMCO Fund may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Underlying PIMCO Fund’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy

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common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. An Underlying PIMCO Fund may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, an Underlying PIMCO Fund may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for an Underlying PIMCO Fund.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time. In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to an Underlying PIMCO Fund as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, an Underlying PIMCO Fund may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, certain Underlying PIMCO Funds may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by an Underlying PIMCO Fund at any given time upon sale thereof, an Underlying PIMCO Fund may determine to hold such securities in its portfolio.
While certain Underlying PIMCO Funds will generally invest in equity derivatives and will not normally invest directly in equity securities, each such Underlying PIMCO Fund may invest without limit directly in equity securities, including common stocks, preferred securities and convertible securities. In addition, the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, each an Underlying PIMCO Fund, may invest in equity securities of issuers in commodity-related industries, and the PIMCO RealEstateRealReturn Strategy Fund, an Underlying PIMCO Fund, may invest in REITs and equity securities of issuers in real estate-related industries. When investing directly in equity securities, an Underlying PIMCO Fund will not be limited to only those equity securities with any particular weighting in such Underlying PIMCO Fund’s respective benchmark index, if any. Generally, the Underlying PIMCO Funds will consider investing directly in equity securities when derivatives on the underlying securities appear to be overvalued.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by an Underlying PIMCO Fund may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
Certain Underlying PIMCO Funds may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a

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non-U.S. country if the issuer of such money market instrument is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, if the issuer of such money market instrument is organized under the laws of a non-U.S. country, or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Underlying PIMCO Funds that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruption, the possibility of security suspensions and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries’ financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on
those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers' financial reporting.
Certain of the Underlying PIMCO Funds also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.Certain Underlying PIMCO Funds may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries within the limitations, if any, set forth in each Underlying PIMCO Fund’s prospectus. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors, and the order in which they are applied may change in the discretion of PIMCO. The current factors listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of

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the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, an Underlying PIMCO Fund emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by an Underlying PIMCO Fund. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause an Underlying PIMCO Fund to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which an Underlying PIMCO Fund’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Underlying PIMCO Fund.
Foreign Currency Transactions.Underlying PIMCO Funds that invest in securities denominated in foreign (non-U.S.) currencies may engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Underlying PIMCO Fund’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Underlying PIMCO Fund is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Underlying PIMCO Fund’s ability to enter into foreign currency transactions, force the Underlying PIMCO Fund to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Underlying PIMCO Fund, any of which may result in a loss to the Underlying PIMCO Fund. A contract to sell a foreign currency would limit any potential gain which might be realized if the value of the hedged currency increases. An Underlying PIMCO Fund may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that an Underlying PIMCO Fund will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for an Underlying PIMCO Fund to benefit from favorable fluctuations in relevant foreign currencies. An Underlying PIMCO Fund may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of

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currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Underlying PIMCO Fund will segregate or “earmark” assets determined to be liquid by PIMCO in accordance with the procedures established by the Board of Trustees (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of an Underlying PIMCO Fund’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, an Underlying PIMCO Fund’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. An Underlying PIMCO Fund may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if an Underlying PIMCO Fund earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Underlying PIMCO Fund’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio and each Underlying PIMCO Fund may enter into repurchase agreements, in which the Portfolio or the Underlying PIMCO Fund purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s or the Underlying PIMCO Fund’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio or the Underlying PIMCO Fund will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
Each Underlying PIMCO Fund may enter into reverse repurchase agreements and dollar rolls, subject to the Underlying PIMCO Fund’s limitations on borrowings. A reverse repurchase agreement involves the
sale of a security by an Underlying PIMCO Fund and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Underlying PIMCO Fund but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, an Underlying PIMCO Fund will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for an Underlying PIMCO Fund.
The Portfolio and Underlying PIMCO Funds may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio or Underlying PIMCO Fund may borrow money from banks for any purpose in an amount up to 1/3 of the Portfolio’s or Underlying PIMCO Fund’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio or Underlying PIMCO Fund may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s or Underlying PIMCO Fund’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
Certain Underlying PIMCO Funds may, but are not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). An Underlying PIMCO Fund may invest some or all of its assets in derivative instruments, subject to the Underlying PIMCO Fund’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by an Underlying PIMCO Fund will succeed. A description of these and other derivative instruments that the Underlying PIMCO Funds may use are described under “Investment Objectives and Policies” in the SAI.
An Underlying PIMCO Fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on an Underlying PIMCO Fund. For example, a small investment in a derivative instrument may have a significant impact on an Underlying PIMCO Fund’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. An Underlying PIMCO Fund may engage in such transactions

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regardless of whether the Underlying PIMCO Fund owns the asset, instrument or components of the index underlying the derivative instrument. An Underlying PIMCO Fund may invest a significant portion of its assets in these types of instruments. If it does, the Underlying PIMCO Fund’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Underlying PIMCO Funds.
CPI Swap. A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk. Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk. The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if an Underlying PIMCO Fund does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk. Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk. Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When an Underlying PIMCO Fund uses derivatives for leverage, investments in
that Underlying PIMCO Fund will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Underlying PIMCO Fund will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability. Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain an Underlying PIMCO Fund’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that an Underlying PIMCO Fund will engage in derivatives transactions at any time or from time to time. An Underlying PIMCO Fund’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk. In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, many of the Underlying PIMCO Funds seek to achieve their investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of these Underlying PIMCO Funds are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent an Underlying PIMCO Fund, or derivatives or other strategies used by the Underlying PIMCO Fund, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Underlying PIMCO Fund and the determination of the NAV value of Underlying PIMCO Fund shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Underlying PIMCO Fund invests; (iv) a fund having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of a fund (due to share purchases or redemptions, for example), potentially resulting in the Underlying PIMCO Fund being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the

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Underlying PIMCO Fund’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks. Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to an Underlying PIMCO Fund’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for an Underlying PIMCO Fund, the Underlying PIMCO Fund might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Underlying PIMCO Fund investments. An Underlying PIMCO Fund may also have to buy or sell a security at a disadvantageous time or price because the Underlying PIMCO Fund is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Underlying PIMCO Fund’s derivative transactions, or impede the employment of the Underlying PIMCO Fund’s derivatives strategies, or adversely affect the Underlying PIMCO Fund’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to an Underlying PIMCO Fund. In addition, an Underlying PIMCO Fund’s use of derivatives may cause the Underlying PIMCO Fund to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Underlying PIMCO Fund had not used such instruments.
A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.The Portfolio may invest in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund. In light of releveant IRS guidance, as discussed above under “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” will seek to gain exposure to the commodity markets primarily through investments in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices, and through investments in its respective Subsidiary (as discussed below). The Underlying
PIMCO Funds may also invest in commodity-linked notes with principal and/or coupon payments linked to the value of particular commodities or commodity futures contracts, or a subset of commodities and commodities futures contracts.
These notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in response to changes in the underlying commodity, commodity futures contract, subset of commodities, subset of commodities futures contracts or commodity index.
These notes expose the Underlying PIMCO Funds economically to movements in commodity prices. These notes also are subject to risks, such as credit, market and interest rate risks, that in general affect the values of debt securities. In addition, these notes are often leveraged, increasing the volatility of each note’s market value relative to changes in the underlying commodity, commodity futures contract or commodity index. Therefore, at the maturity of the note, the Underlying PIMCO Funds may receive more or less principal than it originally invested. The Underlying PIMCO Funds might receive interest payments on the note that are more or less than the stated coupon interest payments.
The Underlying PIMCO Funds may also invest in other commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures. The value of a commodity-linked derivative investment generally is based upon the price movements of a physical commodity (such as energy, mineral, or agricultural products), a commodity futures contract, a subset of commodities, a subset of commodities futures contracts or commodity index, or other economic variable based upon changes in the value of commodities or the commodities markets.
Options transactions may be effected on exchanges or in the OTC market. When OTC options are purchased, an Underlying PIMCO Fund’s portfolio bears the risk that the counterparty that wrote the option will be unable or unwilling to perform its obligations under the option contract. Options may also be illiquid and, in such cases, an Underlying PIMCO Fund may have difficulty closing out its position. OTC options also may include options on baskets of specific securities.
Many swap transactions are privately negotiated agreements between a fund and a counterparty to exchange or swap investment cash flows or assets at specified intervals in the future. The obligations may extend beyond one year. There is often no central exchange for swap transactions and therefore they can be less liquid investments than exchange-traded instruments. The Dodd-Frank Act and related regulatory developments require the clearing and exchange-trading of certain standardized OTC derivative instruments that the CFTC and SEC have defined as “swaps.” The CFTC has implemented mandatory exchange-trading and clearing requirements under the Dodd-Frank Act and the CFTC continues to approve contracts for central clearing. Uncleared swaps are subject to margin requirements that are being implemented on a phased-in basis. The investment adviser will continue to monitor these developments, particularly to the extent regulatory changes affect an Underlying PIMCO Fund’s ability to enter into swap agreements.

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As described below under “Characteristics and Risks of Securities and Investment Techniques-Investments in a Wholly-Owned Subsidiary,” the Underlying PIMCO Funds may gain exposure to commodity markets by investing in their respective Subsidiaries. It is expected that each such Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments.
The IRS issued a revenue ruling that limits the extent to which the Underlying PIMCO Funds may invest directly in commodity-linked swaps or certain other commodity-linked derivatives. The Subsidiaries, on the other hand, may invest in these commodity-linked derivatives generally without limitation. See “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” above for further information.
Investments in a Wholly Owned Subsidiary
Investments in the Subsidiaries by the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, are expected to provide the Underlying PIMCO Funds with exposure to the commodity markets within the limitations of Subchapter M of the Code and recent IRS revenue rulings, as discussed above under “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.”
It is expected that each Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation indexed securities and other Fixed Income Instruments. Although the Underlying PIMCO Funds may enter into these commodity-linked derivative instruments directly, the Underlying PIMCO Funds will likely gain exposure to these derivative instruments indirectly by investing in the their respective Subsidiaries. To the extent that PIMCO believes that these commodity-linked derivative instruments are better suited to provide exposure to the commodities market than commodity index-linked notes, each Underlying PIMCO Fund’s investment in its respective Subsidiary will likely increase. Each Subsidiary will also invest in inflation-indexed securities and/or other Fixed Income Instruments, which are intended to serve as margin or collateral for the Subsidiary’s derivatives position, common and preferred securities as well as convertible securities of issuers in commodity-related industries, collateralized debt obligations, event-linked bonds and event-linked swaps. To the extent that an Underlying PIMCO Fund invests in its respective Subsidiary, it may be subject to the risks associated with those derivative instruments and other securities, which are discussed elsewhere in this prospectus.
While each Subsidiary may be considered similar to an investment company, it is not registered under the 1940 Act and, unless otherwise noted in each Underlying PIMCO Fund’s prospectus, is not subject to all
of the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of an Underlying PIMCO Fund and/or a Subsidiary to operate as described in this prospectus and the SAI and could adversely affect an Underlying PIMCO Fund as well as the Portfolio (to the extent the Portfolio invests in an Underlying PIMCO Fund). Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of an Underlying PIMCO Fund and/or a Subsidiary and result in the Underlying PIMCO Fund underperforming its benchmark index(es).
Real Estate Investment Trusts (REITs)
Certain Underlying PIMCO Funds may invest in REITs. REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
Certain Underlying PIMCO Funds may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.

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Prospectus

ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
Certain Underlying PIMCO Funds may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring an Underlying PIMCO Fund to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that an Underlying PIMCO Fund is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
Each Underlying PIMCO Fund may purchase or sell securities which it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Underlying PIMCO Fund’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Underlying PIMCO Fund’s overall investment exposure. Typically, no income accrues on securities that an Underlying PIMCO Fund has committed to purchase prior to the time delivery of the securities is made, although the Underlying PIMCO Fund may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to
a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio invests substantially all of its assets in other investment companies. The Portfolio’s investment in a particular Underlying PIMCO Fund normally will not exceed 50% of its total assets. An Underlying PIMCO Fund may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio and each Underlying PIMCO Fund may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Each Underlying PIMCO Fund may invest in securities of other investment companies, such as closed-end management investment companies including exchange-traded funds, or in pooled accounts or other investment vehicles which to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The limitation described in the foregoing sentence shall not apply to the investments of the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund in the Subsidiaries. As a shareholder of an investment company or other pooled vehicle, the Portfolio or Underlying PIMCO Funds may indirectly bear service and other fees which are in addition to the fees the Portfolio or Underlying PIMCO Funds pays its service providers.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, each Underlying PIMCO Fund may, in the future and the rules and regulations thereunder and any exemptive relief thereform, elect to pursue its investment objective either by investing directly in securities, or by

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investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Underlying PIMCO Fund.
Small-Cap and Mid-Cap Companies
Certain Underlying PIMCO Funds may invest in equity securities of small-capitalization and mid-capitalization companies, a small-cap company generally considered to be a company with a market capitalization of up to $1.5 billion and a mid-cap company generally considered to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Underlying PIMCO Fund’s investments in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
Each Underlying PIMCO Fund may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose an Underlying PIMCO Fund to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Underlying PIMCO Fund. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”), the Underlying PIMCO Fund must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that an Underlying PIMCO Fund contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. An Underlying PIMCO Fund may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent an Underlying PIMCO Fund engages in short selling in foreign (non-U.S.) jurisdictions, the Underlying PIMCO Fund will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
Each Underlying PIMCO Fund may invest up to 15% of its net assets (5% of total assets in the case of the PIMCO Government Money Market Fund) (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments, and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term
“illiquid investments” for this purpose means investments that an Underlying PIMCO Fund reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by an Underlying PIMCO Fund in a liquidity category other than “illiquid” pursuant to the Underlying PIMCO Fund’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, each Underlying PIMCO Fund may lend its portfolio securities to brokers, dealers, and other financial institutions provided a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When an Underlying PIMCO Fund lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Underlying PIMCO Fund will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. An Underlying PIMCO Fund may pay lending fees to a party arranging the loan. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time an Underlying PIMCO Fund has held a particular security is not generally a consideration in investment decisions. A change in the securities held by an Underlying PIMCO Fund is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, an Underlying PIMCO Fund may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Underlying PIMCO Fund’s portfolio) involves correspondingly greater expenses to an Underlying PIMCO Fund, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect an Underlying PIMCO Fund’s performance. Please see

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Prospectus

the Portfolio’s “Portfolio Summary – Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio and each Underlying PIMCO Fund may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities, in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio or Underlying PIMCO Fund engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s or an Underlying PIMCO Fund’s total net assets may be uninvested. In such cases, Portfolio or Underlying PIMCO Fund assets will be held in cash in the Portfolio’s or Underlying PIMCO Fund’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objectives of the Portfolio and certain Underlying PIMCO Funds are fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval. The investment objectives of certain Underlying PIMCO Funds may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio and Underlying PIMCO Fund investments listed in this prospectus will apply at the time of investment. The Portfolio and each Underlying PIMCO Fund would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. Certain Underlying PIMCO Funds have adopted a policy to invest at least 80% of their assets in investments suggested by their name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. An Underlying PIMCO Fund will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments
held by an Underlying PIMCO Fund could receive a higher rating or a lower rating during the period in which they are held by an Underlying PIMCO Fund. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
An Underlying PIMCO Fund may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Underlying PIMCO Fund may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that a portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Underlying PIMCO Fund invests in high yield and/or unrated securities, the Underlying PIMCO Fund’s success in achieving its investment objective may depend more heavily on the portfolio managers’ creditworthiness analysis than if the Underlying PIMCO Fund invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Underlying PIMCO Funds may invest in other types of securities and use a variety of investment techniques and strategies which are not described in this prospectus. These securities and techniques may subject the Underlying PIMCO Funds to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Underlying PIMCO Funds.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, sub-advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading

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counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Prospectus

Descriptions of the Underlying PIMCO Funds
The Portfolio invests substantially all of its assets in some or all of the Underlying PIMCO Funds, which is defined to include the least expensive class of shares of any actively managed or smart beta funds (including mutual funds or exchange-traded funds) of PIMCO Funds, PIMCO ETF Trust or PIMCO Equity Series, each an affiliated open-end investment company, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. Shares of the PIMCO All Asset: Multi-Real Fund, PIMCO All Asset: Multi-RAE PLUS Fund and PIMCO All Asset: Multi-Short PLUS Fund (the “PAPS All Asset Funds”) may be purchased only by the Portfolio, as well as by the PIMCO All Asset Fund and PIMCO All Asset All Authority Fund, each a series of PIMCO Funds, an affiliated investment company. Because the Underlying PIMCO Funds are not offered in this prospectus, the following provides a general description of the main investments and other information about the Underlying PIMCO Funds. At the discretion of PIMCO and without shareholder approval, the Portfolio may invest in additional Underlying PIMCO Funds created in the future. For a complete description of an Underlying PIMCO Fund, please see that Fund’s Institutional Class or Class M prospectus (or Fund prospectus in the case of any exchange-traded fund of the PIMCO ETF Trust or PIMCO Equity Series, or Fund offering memorandum in the case of the PAPS All Asset Funds), which is incorporated herein by reference and is available free of charge by telephoning 1-800-927-4648.
Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Short Duration
PIMCO Low Duration Income
Short maturity fixed income instruments
0 to 3 years
Max 30% of total
assets below Baa(3)
No Limitation(4)
PIMCO Short Asset Investment
Money market instruments and short maturity
fixed income instruments
≤ 1.5 years
Baa to Aaa
0%
PIMCO Short-Term
Money market instruments and short maturity
fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below Baa
0-10% of total
assets(5)
PIMCO Low Duration
Short maturity fixed income instruments
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration II
Short maturity fixed income instruments with
quality and non-U.S. issuer restrictions
1 to 3 years
A to Aaa
0%
PIMCO Low Duration ESG
Short maturity fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration Credit(10)
Diversified portfolio of fixed income
instruments
0 to 3 years
Max 10% of total
assets below Caa
0-25% of total
assets(11)
Intermediate
Duration
PIMCO Moderate Duration
Short and intermediate maturity fixed income
instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO GNMA and Government
Securities
Short and intermediate maturity
mortgage-related fixed income securities issued
by the Government National Mortgage
Association and U.S. government securities
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa
0%
PIMCO High Yield
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(6); max
20% of total assets
Caa or below
0-20% of total
assets(5)
PIMCO High Yield Spectrum
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(7)
No Limitation(8)
PIMCO Mortgage-Backed Securities
Short and intermediate maturity
mortgage-related fixed income instruments
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa(9)
0%
PIMCO Total Return
Intermediate maturity fixed income instruments
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return II
Intermediate maturity fixed income instruments
with quality and non-U.S. issuer restrictions
+/-2 years of its
benchmark
Baa to Aaa
0%
PIMCO Total Return ESG
Intermediate maturity fixed income instruments
with prohibitions on firms engaged in socially
sensitive practices
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return IV
Intermediate maturity fixed income instruments
+/-1.5 years of its
benchmark
Baa to Aaa
0-15% of total
assets(11)
PIMCO Investment Grade Credit Bond
Investment grade fixed income securities
+/-2 years of its
benchmark
Max 15% of total
assets below Baa
0-30% of total
assets(5)

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Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Long Duration
PIMCO Long Duration Total Return
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Extended Duration
Long-term maturity fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO Long-Term U.S. Government
Long-term maturity fixed income securities
≥ 8 years
A to Aaa; max 25% Aa;
max 10% A
0%
PIMCO Mortgage Opportunities and
Bond
Mortgage-related assets and fixed income
instruments
(-1) to 8 years
Max 50% of total
assets below Baa(12)
0%
PIMCO Long-Term Credit Bond
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
B to Aaa; max 20% of
total assets below Baa
0-30% of total
assets(5)
Income
PIMCO ESG Income
Broad range of fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Income
Broad range of fixed income instruments
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Preferred and Capital Securities
Capital securities and preferred securities
+/-2 years of its
benchmark
No Limitation
No Limitation(4)
Inflation-Related
PIMCO Real Return
Inflation-indexed fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO Long-Term Real Return
Inflation-indexed fixed income securities
+/-4 years of its
benchmark
B to Aaa; max 20% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO CommoditiesPLUS® Strategy
Commodity-linked derivative instruments
backed by an actively managed low volatility
portfolio of fixed income instruments
≤ 1 year
Max 10% of total
assets below Baa
0-20%(4)
PIMCO CommodityRealReturn Strategy®
Commodity-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO RealEstateRealReturn Strategy
Real estate-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO All Asset: Multi-Real
Derivatives linked to real assets complemented
by a portfolio of inflation-linked securities and
other Fixed Income Instruments
≤ 10 years
B to Aaa; max 20%
below Baa(14)
0-30% of total
assets with respect
to the Fund’s
investments in
Fixed Income
Instruments(15)
Tax Exempt
PIMCO California Short Duration
Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal and California
income tax)
≤ 3 years
Caa to Aaa; max 10%
of total assets below
Baa
0%
PIMCO California Municipal Bond
Municipal securities (exempt from federal and
California income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO Short Duration Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal income tax)
≤ 3 years
Baa to Aaa
0%
PIMCO California Intermediate Municipal
Bond
Intermediate maturity municipal securities
(exempt from federal and California income
tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO National Intermediate Municipal
Bond
Municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO New York Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal and New York
income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO High Yield Municipal Bond
Intermediate to long-term maturity high yield
municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
No Limitation
0%

50  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
PIMCO Emerging Markets Bond
Emerging market fixed income instruments
+/- 2 years of its
benchmark
Max 15% of total
assets below B
≥ 80% of assets(16)
PIMCO Emerging Markets Currency and
Short-Term Investments
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and short-term investments
≤ 2 years
Max 15% of total
assets below B
No Limitation(17)
PIMCO International Bond
(U.S. Dollar-Hedged)
Intermediate maturity hedged non-U.S. fixed
income instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO International Bond (Unhedged)
Intermediate maturity non-U.S. fixed income
instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation
PIMCO Global Advantage® Strategy
Bond
U.S. and non-U.S. fixed income instruments
≤ 8 years
Max 15% of total
assets below B
No Limitation
PIMCO Global Bond Opportunities
(U.S. Dollar-Hedged)
U.S. and hedged non-U.S. intermediate maturity
fixed income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO Global Bond Opportunities
(Unhedged)
U.S. and non-U.S. intermediate maturity fixed
income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation
PIMCO Diversified Income
Investment grade corporate, high yield and
emerging market fixed income instruments
3 to 8 years
Max 10% below B
No Limitation
PIMCO Emerging Markets Local Currency
and Bond
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and fixed income instruments
+/-2 years of its
benchmark
Max 15% of total
assets below B
No Limitation(18)
PIMCO Emerging Markets Corporate
Bond
Diversified portfolio of fixed income
instruments economically tied to emerging
market countries
+/- 2 years of its
benchmark
Max 15% of total
assets below B
No Limitation
Absolute Return
PIMCO Dynamic Bond
Diversified portfolio of fixed income
instruments
(-3) to 8 years
Max 40% of total
assets below Baa
No Limitation(19)
PIMCO Strategic Bond
Diversified portfolio of fixed income
instruments
(-1) to 5 years
Max 20% of total
assets below Baa
No Limitation(20)
PIMCO Credit Opportunities Bond
Diversified portfolio of fixed income
instruments
0 to 6 years
Max 50% of total
assets below B-
No Limitation(5)
PIMCO TRENDS Managed Futures
Strategy
Financial and commodity-linked derivative
instruments selected by a quantitative strategy
and generally backed by a short to intermediate
duration portfolio which may consist of cash
equivalent securities and fixed income
instruments
N/A
No Limitation
No Limitation
PIMCO RAE Fundamental Advantage
PLUS
Long exposure to RAE US Large Model
Portfolio, short exposure to the S&P 500 Index,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO Climate Bond
Diversified portfolio of fixed income
instruments
2 to 8 years
Max 25% of total
assets below Baa
No Limitation(5)

April 30, 2021 | PROSPECTUS  51

PIMCO Variable Insurance Trust

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Domestic
Equity-Related
PIMCO RAE PLUS
Exposure to RAE US Large Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO StocksPLUS® Small
Russell 2000® Index derivatives backed by a
diversified portfolio of actively managed fixed
income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(21)
PIMCO StocksPLUS® Long Duration
S&P 500 Index derivatives backed by a
diversified portfolio of long-term fixed income
instruments
+/-2 years of
Bloomberg
Barclays
Long-Term
Government/Credit
Index(22)
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO StocksPLUS® Absolute Return
S&P 500 Index derivatives backed by a portfolio
of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS®
S&P 500 Index derivatives backed by a portfolio
of short-term fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO RAE PLUS Small
Exposure to RAE US Small Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE US
Exposure to RAE US Portfolio
N/A
N/A
0%
PIMCO RAE US Small
Exposure to RAE US Small Portfolio
N/A
N/A
0%
PIMCO RAFI ESG U.S. ETF
Component Securities of the RAFI ESG US Index
N/A
N/A
0%
PIMCO RAFI Dynamic Multi-Factor
U.S. Equity ETF
Component Securities of the RAFI Dynamic
multi-Factor US Index
N/A
N/A
0%
Equity-Related
PIMCO All Asset: Multi-RAE PLUS
Long exposure to a portfolio of stocks
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below Baa
(14)
No Limitation(21)
International
Equity-Related
PIMCO Dividend and Income
Exposure to RAE Income Global Portfolio in
Equity Sleeve; remainder of portfolio invests in
fixed income instruments of varying maturities
N/A
No Limitation
No Limitation
PIMCO RAE PLUS EMG
Exposure to RAE Emerging Markets Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(21)
PIMCO StocksPLUS® International
(Unhedged)
Non-U.S. equity derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(21)
PIMCO StocksPLUS® International
(U.S. Dollar-Hedged)
Non-U.S. equity derivatives (hedged to
U.S. dollars) backed by a portfolio of fixed
income instruments.
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(21)
PIMCO RAE PLUS International
Exposure to RAE International Large Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(11)
PIMCO RAE Worldwide Long/Short PLUS
Long exposure to RAE Low Volatility U.S. Model
Portfolio, RAE Low Volatility Intl Model Portfolio
and RAE Low Volatility EMG Model Portfolio,
short exposure to certain traditional
capitalization-weighted equity indexes,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(11)
PIMCO RAE Emerging Markets
Exposure to RAE Emerging Markets Portfolio
N/A
N/A
No Limitation
PIMCO RAE International
Exposure to RAE International Portfolio
N/A
N/A
No Limitation
PIMCO RAFI Dynamic Multi-Factor
Emerging Markets Equity ETF
Component securities of the RAFI Dynamic
Multi-Factor Emerging Markets Index
N/A
N/A
No Limitation
PIMCO RAFI Dynamic Multi-Factor
International Equity ETF
Component securities of the RAFI Dynamic
Multi-Factor Developed Ex-U.S. Index
N/A
N/A
No Limitation
U.S. Government
Securities
PIMCO Government Money Market
U.S. government securities
≤ 60 days
dollar-weighted
average maturity
Min 97% of total
assets Prime 1; ≤ 3%
of total assets Prime 2
0%

52  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Short Strategies
PIMCO StocksPLUS® Short
Short S&P 500 Index derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO All Asset: Multi-Short PLUS
Short exposure to equity markets
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below Baa
(14)
No Limitation(21)
Actively-Managed
Exchange-Traded
Funds
PIMCO Active Bond Exchange-Traded
Fixed income instruments of varying maturities
2 to 8 years
Max 30% of total
assets below Baa
0-15% of total
assets(4)
PIMCO Enhanced Low Duration Active
Exchange-Traded
Fixed income instruments of varying maturities
1 to 3 years
Max 15% below Baa
No Limitation(11)
PIMCO Enhanced Short Maturity Active
Exchange-Traded
Short to intermediate maturity fixed income
instruments
≤1 year
Baa to Aaa
0%
PIMCO Intermediate Municipal Bond
Active Exchange-Traded
Intermediate maturity municipal securities
(exempt from federal income tax)
(-2) to 4 years of
its benchmark
Baa to Aaa
0%
PIMCO Short Term Municipal Bond Active
Exchange-Traded
Short maturity municipal securities (exempt
from federal income tax)
≤ 3 years
Baa to Aaa
0%
PIMCO Enhanced Short Maturity Active
ESG Exchange-Traded
Short to intermediate maturity fixed income
instruments
≤1 year
Baa to Aaa
0-10% of total
assets
1
As rated by Moody's, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality.
2
Certain Underlying PIMCO Funds may invest beyond these limits in U.S. dollar-denominated instruments of non-U.S. issuers.
3
Such limitation shall not apply to the Fund's investments in mortgage- and asset-backed securities.
4
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 10% of its total assets.
5
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
6
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index.
7
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML Developed Markets High Yield Constrained (USD Hedged) Index.
8
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to within 10% (plus or minus) of the Fund's benchmark's foreign currency exposure.
9
The Fund may also invest up to an additional 5% of its total assets in mortgage-related high yield instruments rated below Baa.
10
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund. Information for the PIMCO Low Duration Credit Fund is effective as of May 3, 2021.
11
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 5% of its total assets.
12
Such limitation shall not apply to the Fund's investments in mortgage-related securities.
13
Within such limitation, the Fund may invest in mortgage-related securities rated below B.
14
Within such limitation, the Fund may invest in mortgage- and asset-backed securities rated below B.
15
With respect to the Fund's fixed income investments, the Fund will normally limit its foreign currency exposure (from non-U.S. dollar denominated securities or currencies) to 20% of its total assets.
16
The percentage limitation relates to Fixed Income Instruments of non-U.S. issuers denominated in any currency.
17
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or in Fixed Income Instruments denominated in the currencies of, emerging market countries, and in short-term investments.
18
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or Fixed Income Instruments denominated in the currencies of, emerging market countries and in Fixed Income Instruments, each of which may be represented by forwards or derivatives such as options, futures contracts or swap agreements.
19
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
20
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 25% of its total assets.
21
With respect to the Fund's fixed income investments, the Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
22
The Bloomberg Barclays Long-Term Government/Credit Index is an unmanaged index of U.S. Government or investment grade credit securities having a maturity of 10 years or more.

April 30, 2021 | PROSPECTUS  53

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO All Asset Portfolio
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$10.92
$0.39
$0.40
$0.79
$(0.50)
$0.00
$0.00
$(0.50)
12/31/2019
10.05
0.32
0.85
1.17
(0.30)
0.00
0.00
(0.30)
12/31/2018
10.97
0.47
(1.06)
(0.59)
(0.33)
0.00
0.00
(0.33)
12/31/2017
10.12
0.47
0.87
1.34
(0.47)
0.00
(0.02)
(0.49)
12/31/2016
9.19
0.21
0.97
1.18
(0.23)
0.00
(0.02)
(0.25)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratios shown do not include expenses of the investment companies in which a Portfolio may invest. See the Fees and Expenses note in the Notes to Financial Statements for more information regarding the expenses and any applicable fee waivers associated with these investments.
(e)
Includes in-kind purchases and sales of underlying funds. Please see Investments in Securities, note in the Notes to Financial Statements for more information.

54  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets(d)
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.21
7.91%
$167,756
0.575%
0.675%
0.575%
0.675%
3.78%
(e)141%
10.92
11.74
180,653
0.525
0.675
0.525
0.675
3.06
31
10.05
(5.45)
178,643
0.555
0.675
0.555
0.675
4.38
37
10.97
13.38
231,030
0.575
0.675
0.575
0.675
4.35
40
10.12
12.90
226,099
0.525
0.675
0.525
0.675
2.12
67

April 30, 2021 | PROSPECTUS  55

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1854F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
Active Asset Allocation Portfolio – Real Return Oriented
PIMCO All Asset Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO All Asset Portfolio

Investment Objective
The Portfolio seeks maximum real return, consistent with preservation of real capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.425%
Acquired Fund Fees and Expenses(1)
0.80%
Total Annual Portfolio Operating Expenses(2)
1.225%
Fee Waiver and/or Expense Reimbursement(3)
(0.10%)
Total Annual Portfolio Operating Expenses After Fee Waiver and/or
Expense Reimbursement
1.125%
1
Acquired Fund Fees and Expenses include interest expense of the Underlying PIMCO Funds of 0.06%. Interest expense can result from certain transactions within the Underlying PIMCO Funds and is separate from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense of the Underlying PIMCO Funds, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 1.065% for Institutional Class shares.
2
Total Annual Portfolio Operating Expenses do not match the Ratio of Expenses to Average Net Assets Excluding Waivers of the Portfolio, as set forth in the Financial Highlights table of the Portfolio’s prospectus, because the Ratio of Expenses to Average Net Assets Excluding Waivers reflects the operating expenses of the Portfolio and does not include Acquired Fund Fees and Expenses.
3
PIMCO has contractually agreed, through May 1, 2022, to reduce its advisory fee to the extent that the Underlying PIMCO Fund Expenses attributable to advisory and supervisory and administrative fees exceed 0.64% of the total assets invested in Underlying PIMCO Funds. PIMCO may recoup these waivers in future periods, not exceeding three years from the date of waiver, provided total expenses, including such recoupment, do not exceed the annual expense limit that was in place at the time the amount being recouped was originally waived and the current annual expense limit. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. The fee reduction is implemented based on a calculation of Underlying PIMCO Fund Expenses attributable to advisory and supervisory and administrative fees that is different from the calculation of Acquired Fund Fees and Expenses listed in the table above.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these
assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$115
$379
$663
$1,474
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 141% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio is a “fund of funds,” which is a term used to describe mutual funds that pursue their investment objective by investing in other funds. The Portfolio seeks to achieve its investment objective by investing under normal circumstances substantially all of its assets in the least expensive class of shares of any actively managed or smart beta funds (including mutual funds or exchange-traded funds) of PIMCO Funds, PIMCO ETF Trust or PIMCO Equity Series, each an affiliated open-end investment company, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management (collectively, “Underlying PIMCO Funds”). As used in the investment objective, “real return” equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure, and “real capital” equals capital less the estimated cost of inflation measured by the change in an official inflation measure. In addition to investing in Underlying PIMCO Funds, at the discretion of PIMCO and without shareholder approval, the Portfolio may invest in additional Underlying PIMCO Funds created in the future.
The Portfolio invests its assets in shares of the Underlying PIMCO Funds and does not invest directly in stocks or bonds of other issuers. Research Affiliates, the Portfolio’s asset allocation sub-adviser, determines how the Portfolio allocates and reallocates its assets among the Underlying PIMCO Funds. In doing so, the asset allocation sub-adviser seeks concurrent exposure to a broad spectrum of asset classes.
Investments in Underlying PIMCO Funds.The Portfolio may invest in any or all of the Underlying PIMCO Funds, but will not normally invest in every Underlying PIMCO Fund at any particular time. The Portfolio’s investment in a particular Underlying PIMCO Fund normally will not exceed 50% of its total assets. The Portfolio will not invest in the Short Strategy Underlying PIMCO Funds, which seek to gain a negative exposure to an asset class such as equities. The Portfolio’s combined investments in the Equity-Related Underlying PIMCO Funds will not exceed 50% of its total assets. In addition, the Portfolio’s combined investments in Inflation-Related Underlying PIMCO Funds, which seek to gain exposure to an asset class such as U.S. Treasury

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Inflation-Protected Securities (“TIPS”), commodities, or real estate, normally will not exceed 75% of its total assets.
Asset Allocation Investment Process.The Portfolio’s assets are not allocated according to a predetermined blend of shares of the Underlying PIMCO Funds. Instead, when making allocation decisions among the Underlying PIMCO Funds, the Portfolio’s asset allocation sub-adviser considers various quantitative and qualitative data relating to the U.S. and foreign economies and securities markets. Such data includes projected growth trends in the U.S. and foreign economies, forecasts for interest rates and the relationship between short- and long-term interest rates (yield curve), current and projected trends in inflation, relative valuation levels in the equity and fixed income markets and various segments within those markets, the outlook and projected growth of various industrial sectors, information relating to business cycles, borrowing needs and the cost of capital, political trends, data relating to trade balances and labor information. The Portfolio’s asset allocation sub-adviser has the flexibility to reallocate the Portfolio’s assets among any or all of the asset class exposures represented by the Underlying PIMCO Funds based on its ongoing analyses of the equity, fixed income and commodity markets. While these analyses are performed daily, material shifts in asset class exposures typically take place over longer periods of time.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Principal Risks of the Portfolio
Allocation Risk:the risk that a Portfolio could lose money as a result of less than optimal or poor asset allocation decisions. The Portfolio could miss attractive investment opportunities by underweighting markets that subsequently experience significant returns and could lose value by overweighting markets that subsequently experience significant declines
Fund of Funds Risk:the risk that a Portfolio’s performance is closely related to the risks associated with the securities and other investments held by the Underlying PIMCO Funds and that the ability of a Portfolio to achieve its investment objective will depend upon the ability of the Underlying PIMCO Funds to achieve their investment objectives
Certain principal risks of investing in the Underlying PIMCO Funds, and consequently the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Certain Principal Risks of Underlying PIMCO Funds
Market Trading Risk:the risk that an active secondary trading market for shares of an Underlying PIMCO Fund that is an exchange-traded fund does not continue once developed, that such Underlying PIMCO Fund may not continue to meet a listing exchange’s trading or listing requirements, or that such Underlying PIMCO Fund’s shares trade at prices other than the Fund’s net asset value
Municipal Project-Specific Risk:the risk that an Underlying PIMCO Fund may be more sensitive to adverse economic, business or political developments if it invests a substantial portion of its assets in the bonds of specific projects (such as those relating to education, health care, housing, transportation, and utilities), industrial development bonds, or in bonds from issuers in a single state
Municipal Bond Risk:the risk that an Underlying PIMCO Fund may be affected significantly by the economic, regulatory or political developments affecting the ability of issuers of debt securities whose interest is, in the opinion of bond counsel for the issuer at the time of issuance, exempt from federal income tax (“Municipal Bonds”) to pay interest or repay principal
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Distressed Company Risk:the risk that securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services

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PIMCO All Asset Portfolio

Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. An Underlying PIMCO Fund’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Underlying PIMCO Fund’s ability to invest in derivatives, limit the Underlying PIMCO Fund’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Underlying PIMCO Fund’s performance
Futures Contract Risk:the risk that, while the value of a futures contract tends to correlate with the value of the underlying asset that it represents, differences between the futures market and the market for the underlying asset may result in an imperfect correlation. Futures contracts may involve risks different from, and possibly greater than, the risks associated with investing directly in the underlying assets. The purchase or sale of a futures contract may result in losses in excess of the amount invested in the futures contract
Model Risk:the risk that an Underlying PIMCO Fund’s investment models used in making investment allocation decisions, and the indexation methodologies used in constructing an underlying index for an Underlying PIMCO Fund that seeks to track the investment results of such underlying index, may not adequately take into account certain factors and may result in a decline in the value of an investment in the Underlying PIMCO Fund
Commodity Risk:the risk that investing in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or
factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Real Estate Risk:the risk that the Portfolio’s investments in Real Estate Investment Trusts (“REITs”) or real estate-linked derivative instruments will subject the Portfolio to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. A Portfolio’s investments in REITs or real estate-linked derivative instruments subject it to management and tax risks. In addition, privately traded REITs subject a Portfolio to liquidity and valuation risk
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Smaller Company Risk:the risk that the value of securities issued by a smaller company may go up or down, sometimes rapidly and unpredictably as compared to more widely held securities, due to narrow markets and limited resources of smaller companies. A Portfolio’s investments in smaller companies subject it to greater levels of credit, market and issuer risk
Issuer Non-Diversification Risk:the risk of focusing investments in a small number of issuers, including being more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Portfolios that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified”
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO, or Research Affiliates, and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO or Research Affiliates to restrict or prohibit participation in certain investments.. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Tax Risk:the risk that the tax treatment of swap agreements and other derivative instruments, such as commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures, may be affected by future regulatory or legislative changes that could affect whether income from such investments is “qualifying income” under Subchapter M of the Internal Revenue Code, or otherwise affect the character, timing and/or amount of the Portfolio’s taxable income or gains and distributions
Subsidiary Risk:the risk that, by investing in certain Underlying PIMCO Funds that invest in a subsidiary (each a “Subsidiary”), the Portfolio is indirectly exposed to the risks associated with a Subsidiary’s investments. The Subsidiaries are not registered under the 1940 Act and may not be subject to all the investor protections of the 1940 Act. There is no guarantee that the investment objective of a Subsidiary will be achieved
Value Investing Risk:a value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
Exchange-Traded Fund Risk:the risk that an exchange-traded fund may not track the performance of the index it is designed to track, among other reasons, because of exchange rules, market prices of shares of an exchange-traded fund may fluctuate rapidly and materially, or shares of an exchange-traded fund may trade significantly above or below net asset value, any of which may cause losses to the Portfolio invested in the exchange-traded fund
Tracking Error Risk:the risk that the portfolio of an Underlying PIMCO Fund that seeks to track the investment results of an underlying index may not closely track the underlying index for a number of reasons. The Underlying PIMCO Fund incurs operating expenses, which are not applicable to the underlying index, and the costs of buying and selling securities, especially when rebalancing the Underlying PIMCO Fund’s portfolio to reflect changes in the composition of the underlying index. Performance of the Underlying PIMCO Fund and the underlying index may vary due to asset valuation differences and differences between the Underlying PIMCO Fund’s portfolio and the underlying index due to legal restrictions, cost or liquidity restraints. The risk that performance of the Underlying PIMCO Fund and the underlying index may vary may be heightened during periods of increased market volatility or other unusual market conditions. In addition, an Underlying PIMCO Fund’s use of a representative sampling approach may cause the Underlying PIMCO Fund to be less correlated to the return of the underlying index than if the Underlying PIMCO Fund held all of the securities in the underlying index
Indexing Risk:the risk that an Underlying PIMCO Fund that seeks to track the investment results of an underlying index is negatively affected by general declines in the asset classes represented by the underlying index
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by an Underlying PIMCO Fund rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Underlying PIMCO Fund or on certain instruments in which the Underlying PIMCO Fund invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in value of certain instruments held by the Underlying PIMCO Fund
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

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PIMCO All Asset Portfolio

Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index and an index of similar funds. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio measures its performance against a primary benchmark and a secondary benchmark. The Bloomberg Barclays U.S. TIPS: 1-10 Year Index, the primary benchmark, is an unmanaged index comprised of U.S. Treasury Inflation-Protected securities having a maturity of at least 1 year and less than 10 years. The CPI + 500 Basis Points benchmark, the secondary benchmark, is created by adding 5% to the annual percentage change in the Consumer Price Index (“CPI”). The CPI is an unmanaged index representing the rate of inflation of the U.S. consumer prices as determined by the U.S. Bureau of Labor Statistics.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class
Best Quarter
June 30, 2020
12.21%
Worst Quarter
March 31, 2020
-16.09%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Institutional Class Return
8.17%
8.10%
4.80%
Bloomberg Barclays U.S. TIPS: 1-10 Year Index (reflects
no deductions for fees, expenses or taxes)
8.39%
4.13%
2.88%
Consumer Price Index + 500 Basis Points (reflects no
deductions for fees, expenses or taxes)
6.29%
6.94%
6.73%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. Research Affiliates serves as the asset allocation sub-adviser to the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Robert D. Arnott and Christopher J. Brightman. Mr. Arnott is the Chairman and Founder of Research Affiliates and he has managed the Portfolio since its inception in April 2003. Mr. Brightman is Chief Investment Officer of Research Affiliates and he has managed the Portfolio since November 2016.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

5  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments in the Underlying PIMCO Funds. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Underlying PIMCO Funds, and consequently the Portfolio, are identified in the Portfolio Summary and are described in this section. The Portfolio and the Underlying PIMCO Funds may be subject to additional risks other than those identified and described below because the types of investments made by an Underlying PIMCO Fund can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Underlying PIMCO Funds, their investments and the related risks. There is no guarantee that the Portfolio or the Underlying PIMCO Funds will be able to achieve their investment objectives. It is possible to lose money by investing in the Portfolio.
Allocation Risk
The Portfolio’s investment performance depends upon how its assets are allocated and reallocated between the Underlying PIMCO Funds according to the Portfolio’s asset allocation targets and ranges. A principal risk of investing in the Portfolio is that the asset allocation sub-adviser will make less than optimal or poor asset allocation decisions. The asset allocation sub-adviser attempts to identify investment allocations for the Underlying PIMCO Funds that will provide consistent, quality performance for the Portfolio, but there is no guarantee that such allocation techniques will produce the desired results. It is possible that the asset allocation sub-adviser will focus on an Underlying PIMCO Fund that performs poorly or underperforms other Underlying PIMCO Funds under various market conditions. You could lose money on your investment in the Portfolio as a result of these allocation decisions.
Fund of Funds Risk
Because the Portfolio invests substantially all of its assets in Underlying PIMCO Funds, the risks associated with investing in the Portfolio are closely related to the risks associated with the securities and other investments held by the Underlying PIMCO Funds. The ability of the Portfolio to achieve its investment objective will depend upon the ability of the Underlying PIMCO Funds to achieve their respective investment objectives. There can be no assurance that the investment objective of any Underlying PIMCO Fund will be achieved.
The Portfolio’s net asset value (“NAV”) will fluctuate in response to changes in the respective NAVs of the Underlying PIMCO Funds in which it invests. The extent to which the investment performance and risks associated with the Portfolio correlate to those of a particular Underlying PIMCO Fund will depend upon the extent to which the Portfolio’s assets are allocated from time to time for investment in the Underlying PIMCO Fund, which will vary. To the extent that the Portfolio invests a significant portion of its assets in an Underlying PIMCO Fund, it will be particularly sensitive to the risks associated with that Underlying PIMCO Fund.
Market Trading Risk
An Underlying PIMCO Fund that is an exchange-traded fund is subject to secondary market trading risks. Once operational, shares of the Underlying PIMCO Fund are listed for trading on an exchange, however, there can be no guarantee that an active trading market for such shares will develop or continue. Shares of the Underlying PIMCO Fund may be listed or traded on U.S. and foreign (non-U.S.) exchanges other than the Underlying PIMCO Fund’s primary U.S. listing exchange. There can be no guarantee that the Underlying PIMCO Fund’s shares will continue trading on any exchange or in any market or that the Underlying PIMCO Fund’s shares will continue to meet the listing or trading requirements of any exchange or market. The Underlying PIMCO Fund’s shares may experience higher trading volumes on one exchange as compared to another and investors are subject to the execution and settlement risks of the market where their broker directs trades.
Secondary market trading in the Underlying PIMCO Fund’s shares may be halted by an exchange because of market conditions. Pursuant to exchange or market rules, trading in the Underlying PIMCO Fund’s shares on an exchange or in any market may be subject to trading halts caused by extraordinary market volatility. If secondary market trading is halted or an exchange closes earlier than anticipated, you may be unable to purchase or sell Portfolio shares. There can be no guarantee that the Underlying PIMCO Fund’s exchange listing or ability to trade its shares will continue or remain unchanged. In the event the Underlying PIMCO Fund ceases to be listed on an exchange, the Underlying PIMCO Fund may cease operating as an “exchange-traded” fund and operate as a mutual fund, provided that shareholders are given advance notice.
Buying or selling the Underlying PIMCO Fund’s shares on an exchange may require the payment of brokerage commissions. In addition, an investor who buys or sells the Underlying PIMCO Fund’s shares may also incur the cost of the spread (the difference between the bid price and the ask price). The commission is frequently a fixed amount and may be a significant cost for investors seeking to buy or sell small amounts of shares. The spread varies over time for shares of the Underlying PIMCO Fund based on their trading volume and market liquidity, and is generally less if the Underlying PIMCO Fund has more trading volume and market liquidity and more if the Underlying PIMCO Fund has less trading volume and market liquidity. Due to the costs inherent in buying or selling the Underlying PIMCO Fund’s shares, frequent trading may detract significantly from investment returns. Investment in the Underlying PIMCO Fund’s shares may not be advisable for investors who expect to engage in frequent trading.

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Shares of the Underlying PIMCO Fund may trade on an exchange at prices at, above or below their most recent NAV. The market prices of an Underlying PIMCO Fund’s shares will fluctuate, sometimes rapidly and materially, in response to changes in the Underlying PIMCO Fund’s NAV, the value of the Underlying PIMCO Fund’s holdings and supply and demand for the Underlying PIMCO Fund’s shares. Although the creation/redemption feature of the Underlying PIMCO Funds generally makes it more likely that an Underlying PIMCO Fund’s shares will trade close to NAV, market volatility, lack of an active trading market for the Underlying PIMCO Fund’s shares, disruptions at market participants (such as authorized participants or market makers) and any disruptions in the ordinary functioning of the creation/redemption process may result in the Underlying PIMCO Fund’s shares trading significantly above (at a “premium”) or below (at a “discount”) NAV. An investor who buys or sells an Underlying PIMCO Fund’s shares may incur significant losses if the investor transacts in the Underlying PIMCO Fund’s shares in these and other circumstances. Neither PIMCO nor the Trust can predict whether an Underlying PIMCO Fund’s shares will trade above, below or at NAV. An Underlying PIMCO Fund’s investment results are based on the Underlying PIMCO Fund’s daily NAV. Investors transacting in an Underlying PIMCO Fund’s shares in the secondary market, where market prices may differ from NAV, may experience investment results that differ from results based on the Underlying PIMCO Fund’s daily NAV.
Municipal Project-Specific Risk
An Underlying PIMCO Fund may be more sensitive to adverse economic, business or political developments if it invests a substantial portion of its assets in the bonds of specific projects (such as those relating to education, health care, housing, transportation, and utilities), industrial development bonds, or in general obligation bonds, particularly if there is a large concentration from issuers in a single state.
Municipal Bond Risk
An Underlying PIMCO Fund that invests in Municipal Bonds may be affected significantly by the economic, regulatory or political developments affecting the ability of issuers of Municipal Bonds to pay interest or repay principal. In addition, the ability of an issuer to make payments or repay interest may be affected by litigation or bankruptcy. In the event of bankruptcy of such an issuer, an Underlying PIMCO Fund investing in the issuer’s securities could experience delays in collecting principal and interest, and the Underlying PIMCO Fund may not, in all circumstances, be able to collect all principal and interest to which it is entitled. To enforce its rights in the event of a default in the payment of interest or repayment of principal, or both, an Underlying PIMCO Fund may, in some instances, take possession of, and manage, the assets securing the issuer’s obligations on such securities, which may increase the Underlying PIMCO Fund’s operating expenses. Any income derived from the Underlying PIMCO Fund’s ownership or operation of such assets may not be tax-exempt. Municipal Bonds are subject to interest rate, credit and market risk.
Because many Municipal Bonds are issued to finance similar projects (such as those relating to education, health care, housing, transportation, and utilities), conditions in those sectors may affect the overall municipal securities market. In addition, changes in the financial condition of an individual municipal issuer can affect the overall municipal market. Municipal Bonds backed by current or anticipated revenues from a specific project or specific assets can be negatively affected by the discontinuance of the supporting taxation or the inability to collect revenues for the specific project or specific assets. Municipal Bonds are subject to the risk that the Internal Revenue Service (“IRS”) may determine that an issuer has not complied with applicable tax requirements and that interest from the Municipal Bond is taxable, which may result in a significant decline in the value of the security. Municipal Bonds may be less liquid than taxable bonds and there may be less publicly available information on the financial condition of Municipal Bond issuers than for issuers of other securities, and the investment performance of an Underlying PIMCO Fund investing in Municipal Bonds may therefore be more dependent on the analytical abilities of PIMCO than if the Underlying PIMCO Fund held other types of investments such as stocks or taxable bonds. The secondary market for Municipal Bonds also tends to be less well-developed or liquid than many other securities markets, a by-product of lower capital commitments to the asset class by the dealer community, which may adversely affect an Underlying PIMCO Fund’s ability to sell Municipal Bonds it holds at attractive prices or value Municipal Bonds.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in an Underlying PIMCO Fund’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Underlying PIMCO Fund is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and an Underlying PIMCO Fund may lose money as a result of movements in interest rates. An Underlying PIMCO Fund may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.

April 30, 2021 | PROSPECTUS  7

PIMCO Variable Insurance Trust

Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When an Underlying PIMCO Fund holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Underlying PIMCO Fund’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Underlying PIMCO Fund may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Underlying PIMCO Fund is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Underlying PIMCO Fund. This is especially the case if the Underlying PIMCO Fund consists of securities with widely varying durations. Therefore, if the Underlying PIMCO Fund has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Underlying PIMCO Fund uses leverage or derivatives in connection with the management of the Underlying PIMCO Fund.
Convexity is an additional measure used to understand a security’s or an Underlying PIMCO Fund‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Underlying PIMCO Fund holds such securities, the Underlying PIMCO Fund may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
An Underlying PIMCO Fund could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/ or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by an Underlying PIMCO Fund may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Underlying PIMCO Fund. This is especially the case if the Underlying PIMCO Fund consists of securities with widely varying credit ratings. Therefore, if the Underlying PIMCO Fund has an average credit rating that suggests a certain credit quality, the Underlying PIMCO Fund may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Underlying PIMCO Fund uses leverage or derivatives in connection with the management of the Underlying PIMCO Fund. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/ or interest.

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Prospectus

High Yield Risk
Underlying PIMCO Funds that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Distressed Company Risk
An Underlying PIMCO Fund that invests in securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments. Issuers of distressed company securities may also be involved in restructurings or bankruptcy proceedings that may not be successful. An economic downturn or period of rising interest rates could adversely affect the market for these securities and reduce the Underlying PIMCO Fund’s ability to sell these securities (liquidity risk). If the issuer of a debt security is in default with respect to interest or principal payments, the Underlying PIMCO Fund may lose its entire investment.
Market Risk
The market price of securities owned by an Underlying PIMCO Fund may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors which affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by an Underlying PIMCO Fund. Even when markets perform well, there is no assurance that the investments held by an Underlying PIMCO Fund will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Underlying PIMCO Funds to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Underlying PIMCO Funds’ investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi- governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the

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ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent an Underlying PIMCO Fund from executing advantageous investment decisions in a timely manner. Underlying PIMCO Funds that have focused their investments in a region enduring geopolitical market disruption will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to an Underlying PIMCO Fund’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Underlying PIMCO Fund to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause an Underlying PIMCO Fund to lose enough value, the Underlying PIMCO Fund could also face increased shareholder redemptions, which could force the Underlying PIMCO Fund to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Underlying PIMCO Fund.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, an Underlying PIMCO Fund being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAVs, delays in NAV calculation and/or the inability to calculate NAVs over extended periods.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Underlying PIMCO Funds reasonably expect cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. An Underlying PIMCO Fund’s investments in illiquid investments may reduce the returns of the Underlying PIMCO Fund because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Underlying PIMCO Fund to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Underlying PIMCO Fund from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, an Underlying PIMCO Fund, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that an Underlying PIMCO Fund principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Underlying PIMCO Fund will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for an Underlying PIMCO Fund to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require an Underlying PIMCO Fund to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Underlying PIMCO Fund, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.

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Prospectus

Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Underlying PIMCO Funds may use are referenced under “Characteristics and Risks of Securities and Investment Techniques-Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. Underlying PIMCO Funds may also use derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. Underlying PIMCO Funds may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject an Underlying PIMCO Fund to the potential for unlimited loss. The use of derivatives may cause the Underlying PIMCO Fund’s investment returns to be impacted by the performance of securities the Underlying PIMCO Fund does not own and result in the Underlying PIMCO Fund’s total investment exposure exceeding the value of its portfolio.
An Underlying PIMCO Fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of the derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Underlying PIMCO Fund may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Underlying PIMCO Fund are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Underlying PIMCO Fund, or the derivatives or other strategies used by the Underlying PIMCO Fund, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Underlying PIMCO Fund invests. By investing in a derivative instrument, the Underlying PIMCO Fund could lose more than the initial amount invested, and derivatives may increase the volatility of the Underlying PIMCO Fund, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that an Underlying PIMCO Fund will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, an Underlying PIMCO Fund’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders.
Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Underlying PIMCO Fund’s clearing broker, or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which an Underlying PIMCO Fund may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If an Underlying PIMCO Fund incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Underlying PIMCO Fund might have been in a better position if the Underlying PIMCO Fund had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Underlying PIMCO Fund and its counterparty. Therefore, it may not be possible for an Underlying PIMCO Fund to modify, terminate, or offset the Underlying PIMCO Fund’s obligations or the Underlying PIMCO Fund’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Underlying PIMCO Fund. In such case, the Underlying PIMCO Fund may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, an Underlying PIMCO Fund may wish to retain the Underlying PIMCO Fund’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, an Underlying PIMCO Fund will be subject to increased liquidity and investment risk.

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When a derivative is used as a hedge against a position that an Underlying PIMCO Fund holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that an Underlying PIMCO Fund’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of an Underlying PIMCO Fund’s derivative transactions, impede the employment of the Underlying PIMCO Fund’s derivatives strategies, or adversely affect the Underlying PIMCO Fund’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Underlying PIMCO Funds' asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Underlying PIMCO Funds to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Underlying PIMCO Funds to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Underlying PIMCO Funds' ability to employ certain strategies that use these instruments and/or adversely affect the Underlying PIMCO Funds' performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Underlying PIMCO Funds' investments and cost of doing business, which could adversely affect investors.
Futures Contract Risk
A futures contract is an exchange-traded contract to buy or sell an underlying asset, such as a security, currency or commodity, for a set price on a future date. The risks associated with the Underlying PIMCO Fund’s use of derivative instruments, including futures contracts, are discussed in more detail under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and under “Investment Objectives and Policies” in the SAI. The purchase or sale of a futures contract may result in losses in excess of the amount invested in the futures contract. There can be no guarantee that there will be a correlation between price movements in the futures contract and the underlying asset. In addition, there are significant differences between the futures market and the markets for underlying assets, which could result in an imperfect correlation between the markets. The degree of imperfect correlation depends on circumstances such as variations in speculative market demand for futures and futures options on underlying assets, including technical influences in futures trading and futures options, and differences between the futures contract and underlying asset due to factors such as interest rate levels, maturities, and creditworthiness of issuers.
Futures contracts are traded on exchanges, so that, in most cases, a party can close out its position on the exchange for cash, without delivering the underlying asset. Because the futures utilized by certain Underlying PIMCO Funds are exchange-traded, the primary credit risk on futures contracts resides with the Underlying PIMCO Fund’s clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Underlying PIMCO Fund’s ability to invest in derivatives, limit an Underlying PIMCO Fund’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Underlying PIMCO Funds performance. Futures exchanges may limit the amount of fluctuation permitted in certain futures contract prices during a single trading day. There can be no assurance that a liquid market will exist at a time when an Underlying PIMCO Fund seeks to close out a futures or a futures option position, and that the Portfolio or Underlying PIMCO Fund would remain obligated to meet margin requirements until the position is closed.
In addition, certain futures contracts may be relatively new instruments without a significant trading history. As a result, there can be no assurance that an active secondary market will develop or continue to exist.
Model Risk
In making investment allocation decisions for a Portfolio or certain Underlying PIMCO Funds, as applicable, PIMCO or the Sub-Adviser, as applicable, may utilize quantitative models that may be proprietary or developed by third-parties. These models are used by PIMCO or the Sub-Adviser, as applicable, to determine (or assist in determining) the Portfolio’s or Underlying PIMCO Fund’s target asset allocation and to identify potentially attractive relative value and risk hedging strategies. The investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in a Portfolio or Underlying PIMCO Fund. There can be no assurance that the models used by PIMCO or the Sub-Adviser, as applicable, will remain viable, due to various factors, which may include the quality of the data input into the models and the assumptions underlying such models, which to varying degrees involve the exercise of judgment, as well as the possibility of errors in constructing or using the model. In addition, in constructing the underlying index of, or model portfolio for, an Underlying PIMCO Fund that seeks to track the investment results of such underlying index or model portfolio, the index provider or sub-adviser, as applicable, may utilize quantitative models or

12  Prospectus | PIMCO Variable Insurance Trust

Prospectus

methodologies that may be proprietary or developed by third-parties. These models and methodologies are used to help determine the composition of the underlying index or model portfolio and may not adequately take into account certain factors, resulting in a decline in the value of the underlying index or model portfolio and, therefore, the Underlying PIMCO Fund.
Models rely on accurate market data inputs. If inaccurate market data is entered into a model, the resulting information will be incorrect. In addition, the models used may be predictive in nature and such models may result in an incorrect assessment of future events. The models evaluate securities or securities markets based on certain assumptions concerning the interplay of market factors. The markets or the prices of individual securities may be affected by factors not foreseen in developing the models. In addition, when relying on a quantitative model and/or data supplied by third parties, PIMCO or the Sub-Adviser may have less insight into the construction, coding or testing of the third-party model or data, and PIMCO and the Sub-Adviser will be exposed to systems, cyber security and other risks associated with the third party that provides the model or data.
The use of models can be complex and involves financial, economic, econometric and statistical theories, research and modeling; and the results of those processes must then be translated into computer code. Although PIMCO and the Sub-Adviser seek to hire individuals and/or third parties, as applicable, skilled in each of these functions and to provide appropriate levels of oversight, the complexity of the individual tasks, the difficulty of integrating such tasks, and the limited ability to perform “real world” testing of a model’s end product raises the chances that a finished model may contain an error; one or more of such errors could adversely affect a Portfolio’s or an Underlying PIMCO Fund’s performance.
Commodity Risk
An Underlying PIMCO Fund’s investments in commodity-linked derivative instruments may subject the Underlying PIMCO Fund to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments. Certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund® , may each concentrate its assets in a particular sector of the commodities market (such as oil, metal or agricultural products). As a result, to the extent the Portfolio invests in the PIMCO CommoditiesPLUS® Strategy Fund or PIMCO CommodityRealReturn Strategy Fund® , each an Underlying PIMCO Fund, the Portfolio may be more susceptible to risks associated with those sectors. The prices for commodities in those sectors may fluctuate widely due to factors such as changes in value, supply and demand and governmental regulatory policies.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if an Underlying PIMCO Fund holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing an Underlying PIMCO Fund to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an Underlying PIMCO Fund to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of an Underlying PIMCO Funds because the Underlying PIMCO Fund may have to reinvest that money at the lower prevailing interest rates. An Underlying PIMCO Fund’s investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
Certain Underlying PIMCO Funds may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than portfolios that invest exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers.
Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Underlying PIMCO Fund’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Underlying PIMCO Fund could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that an Underlying PIMCO Fund invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Underlying PIMCO Fund will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Real Estate Risk
Underlying PIMCO Funds that invest in real estate investment trusts (“REITs”) or real estate-linked derivative instruments are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. An investment in a REIT or a real estate-linked derivative instrument that is linked to the value of a REIT is subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (the “Code”). In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. Finally, private REITs are not traded on a national securities exchange. As such, these products are generally illiquid. This reduces the ability of an Underlying PIMCO Fund to redeem its investment early. Private REITs are also generally harder to value and may bear higher fees than public REITs
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent an Underlying PIMCO Fund invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, technical, political and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent an Underlying PIMCO Fund invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Underlying PIMCO Fund may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. An Underlying PIMCO Fund that focuses its investments in multiple asset classes of emerging marketsecurities may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. An Underlying PIMCO Fund may also be subject to Emerging Markets Risk if they invest in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Underlying PIMCO Funds could lose money the economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers of such emerging markets may be more affected by the performance of such industries or sectors..

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Prospectus

Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If an Underlying PIMCO Fund invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, an Underlying PIMCO Fund’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that an Underlying PIMCO Fund invests in foreign (non-U.S.)currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Issuer Non-Diversification Risk
Focusing investments in a small number of issuers increases risk. Underlying PIMCO Funds that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than Underlying PIMCO Funds that are “diversified.” Underlying PIMCO Funds that invest in a relatively small number of issuers are more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Some of those issuers also may present substantial credit or other risks.
To the extent that the Portfolio invests a significant portion of its assets in an Underlying PIMCO Fund, the Portfolio will be particularly sensitive to the risks associated with that Underlying PIMCO Fund. For a discussion of risks associated with Underlying PIMCO Funds, please see “Fund of Funds Risk” above.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate its leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. Underlying PIMCO Funds also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause an Underlying PIMCO Fund to liquidate portfolio positions to satisfy its obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause an Underlying PIMCO Fund to be more volatile than if the Underlying PIMCO Fund had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Underlying PIMCO Fund’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Underlying PIMCO Fund does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where an Underlying PIMCO Fund, for any reason, is unable to close out the transaction. In addition, to the extent an Underlying PIMCO Fund borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed an Underlying PIMCO Fund’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, an Underlying PIMCO Fund may be forced to sell portfolio securities when it is not otherwise advantageous to do so.

April 30, 2021 | PROSPECTUS  15

PIMCO Variable Insurance Trust

Smaller Company Risk
The general risks associated with fixed income securities and equity securities are particularly pronounced for securities issued by companies with smaller market capitalizations. These companies may have limited product lines, markets or financial resources or they may depend on a few key employees. As a result, they may be subject to greater levels of credit, market and issuer risk. Securities of smaller companies may trade less frequently and in lesser volumes than more widely held securities and their values may fluctuate more sharply than other securities. Companies with medium-sized market capitalizations may have risks similar to those of smaller companies.
Management Risk
Certain Underlying PIMCO Funds are subject to management risk because they are actively managed investment portfolios. PIMCO or the Sub-Adviser, as applicable, and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Underlying PIMCO Funds, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which an Underlying PIMCO Fund seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Underlying PIMCO Fund. To the extent the Underlying PIMCO Fund employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Underlying PIMCO Fund. Certain Underlying PIMCO Funds are also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Underlying PIMCO Fund or hinder Underlying PIMCO Fund operations. For example, trading delays or errors (both human and systematic) could prevent an Underlying PIMCO Fund from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Underlying PIMCO Funds and may also adversely affect the ability of the Underlying PIMCO Funds to achieve their investment objectives. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on an Underlying PIMCO Fund’s ability to realize its investment objective.
Because a number of Underlying PIMCO Funds obtain exposure to certain proprietary model stock portfolios by investing in equity total return swaps based on such model portfolios, in other securities and instruments to replicate the performance of such model portfolios, or directly in the equity securities held in such model portfolios, such Underlying PIMCO Funds will be subject to the risks associated with the management of these proprietary model stock portfolios by the sub-adviser to such Underlying PIMCO Funds. Similarly, there can be no assurance that quantitative models or methods utilized by PIMCO or the Sub-Adviser or related data sources will always be available, and the loss of access to any such model(s) or data sources could have an adverse impact on the Underlying PIMCO Fund's ability to realize its investment objective.
Short Exposure Risk
An Underlying PIMCO Fund’s short sales, if any, are subject to special risks. A short sale involves the sale by the Underlying PIMCO Fund of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. An Underlying PIMCO Fund may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Underlying PIMCO Fund will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, an Underlying PIMCO Fund could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase an Underlying PIMCO Fund’s exposure to long security positions and make any change in the Underlying PIMCO Fund’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy an Underlying PIMCO Fund employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, an Underlying PIMCO Fund may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Underlying PIMCO Fund.

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Prospectus

Tax Risk
The PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund in which the Portfolio may invest, gain exposure to the commodities markets through investments in commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures. The PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund may also gain exposure indirectly to commodity markets by investing in their respective subsidiaries (the “Subsidiaries”), which invest primarily in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and/or other Fixed Income Instruments. In order for each Underlying PIMCO Fund to qualify as a regulated investment company under Subchapter M of the Code, the Underlying PIMCO Fund must derive at least 90 percent of its gross income each taxable year from certain qualifying sources of income.
As more fully described below under “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” the IRS issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. The IRS has issued private letter rulings in which the IRS specifically concluded that income derived from the Underlying PIMCO Fund’s investment in its Subsidiary will also constitute qualifying income to each Underlying PIMCO Fund. Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if an Underlying PIMCO Fund‘s income from an investment in the subsidiary is distributed annually or is derived with respect to the Underlying PIMCO Fund’s business of investing in securities. An IRS revenue procedure states that the IRS will issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the Investment Company Act of 1940, as amended (the “1940 Act”).
Each Underlying PIMCO Fund will seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in its respective Subsidiary. If the IRS were to determine that income derived from certain commodity-linked notes or from investments in the Subsidiary does not constitute qualifying income, the Portfolio and certain Underlying PIMCO Funds, including the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund, might be adversely affected and would be required to reduce their exposure to such investments which might result in difficulty in implementing their investment strategies and increased costs and taxes. The use of commodity index-linked notes and investments in the Subsidiaries involve specific risks. See “Characteristics and Risks of Securities and Investment Techniques-Derivatives-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” below for further information regarding commodity index-linked notes, including the risks associated with these instruments. In addition, see “Characteristics and Risks of Securities and Investment Techniques-Investments in a Wholly-Owned Subsidiary” below for further information regarding the Subsidiaries, including the risks associated with investing in the Subsidiaries.
To the extent the Portfolio invests in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund®, or PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, the use of the above noted investments by the Underlying PIMCO Fund could subject the shareholders of the Portfolio to risks similar to those borne by shareholders of the PIMCO CommodityRealReturn® Strategy and PIMCO Global Managed Asset Allocation Portfolios. See “Tax Consequences.”
Subsidiary Risk
By investing in their respective Subsidiaries, the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund, Underlying PIMCO Funds, are indirectly exposed to the risks associated with the respective Subsidiary’s investments. The investments held by the Subsidiaries are generally similar to those that are permitted to be held by these Underlying PIMCO Funds and are subject to the same risks that apply to similar investments if held directly by the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund or PIMCO TRENDS Managed Futures Strategy Fund. These risks are described elsewhere in this prospectus. There can be no assurance that the investment objectives of the Underlying PIMCO Funds or the Subsidiaries will be achieved.
The Subsidiaries are not registered under the 1940 Act, and, unless otherwise noted in this prospectus, are not subject to all the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund and/or the Subsidiaries to operate as described in this prospectus and the SAI and could adversely affect the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund and, to the extent the Portfolio invests in the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund, the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of an Underlying PIMCO Fund and/or a Subsidiary and result in the Underlying PIMCO Fund underperforming its benchmark index(es).

April 30, 2021 | PROSPECTUS  17

PIMCO Variable Insurance Trust

Value Investing Risk
Value investing attempts to identify companies that are believed to be undervalued. Value stocks typically have prices that are low relative to factors such as the company’s earnings, cash flow or dividends. A value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur. A value investing style may perform better or worse than equity portfolios that focus on growth stocks or that have a broader investment style.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.
Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
Exchange-Traded Fund (“ETF”) Risk
Investments in ETFs entail certain risks. Investments in ETFs designed to track an index involve the risk that the ETF’s performance may not track the performance of the index the ETF is designed to track. This deviation may occur due to cash inflows and outflows from and to investors buying and redeeming shares or due to occasional differences between the composition of the index and the securities held by the ETF. In addition, investments in ETFs involve the risk that the market prices of ETF shares will fluctuate, sometimes rapidly and materially, in response to changes in the ETF’s NAV, the value of ETF holdings and supply and demand for ETF shares. Although ETFs will generally trade close to NAV, market volatility, lack of an active trading market for ETF shares, disruptions at market participants (such as Authorized Participants or market makers) and any disruptions in the ordinary functioning of the creation/redemption process may result in ETF shares trading significantly above (at a “premium”) or below (at a “discount”) NAV. Significant losses may result when transacting in ETF shares in these and other circumstances.
Tracking Error Risk
An Underlying PIMCO Fund that seeks to track the investment results of an index may not invest in every component security of its underlying index. Imperfect correlation between an Underlying PIMCO Fund’s portfolio and its underlying index, asset valuation, timing variances, changes to the underlying index and regulatory requirements may cause the Underlying PIMCO Fund’s performance to diverge from the performance of its underlying index. Tracking error may also result because an Underlying PIMCO Fund incurs fees and expenses while its underlying index does not incur such fees and expenses. Such expenses include the costs of buying and selling securities, such as when an Underlying PIMCO Fund rebalances its portfolio to reflect changes in the composition of the underlying index. These expenses may be higher for an Underlying PIMCO Fund investing in foreign (non-U.S.) securities. The performance of an Underlying PIMCO Fund and the underlying index may vary due to differences between the Underlying PIMCO Fund’s portfolio and the underlying index due to legal restrictions, cost or liquidity restraints. The risk that performance of an Underlying PIMCO Fund and the underlying index may vary may be heightened during periods of market volatility or other unusual market conditions. Because an underlying index is not subject to the tax diversification requirements to which an Underlying PIMCO Fund must adhere, the Underlying PIMCO Fund may be required to deviate its investments from the securities and relative weightings of its underlying index. For tax efficiency purposes, an Underlying PIMCO Fund may sell certain securities to realize losses, which will result in a deviation from its underlying index. An Underlying PIMCO Fund may not be fully invested at times either as a result of cash flows into the Fund or reserves of cash held by the Fund to meet redemptions and to

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

pay expenses. In addition, if an Underlying PIMCO Fund uses a representative sampling approach, this approach may cause the Underlying PIMCO Fund to be less correlated with the return of the underlying index than if the Underlying PIMCO Fund held all of the securities in the underlying index with the same relative weightings as the underlying index.
Indexing Risk
Certain Underlying PIMCO Funds use an indexing approach and may be affected by a general decline in market segments or asset classes relating to their underlying indexes. Those Underlying PIMCO Funds invest in securities and instruments included in, or representative of, their underlying indexes regardless of the investment merits of the underlying indexes. Additionally, errors in the construction or calculation of an Underlying PIMCO Fund’s underlying index may occur from time to time, and the index provider may not identify or correct such errors for some period of time. Any such underlying index construction or calculation error may adversely impact the Underlying PIMCO Fund.
LIBOR Transition Risk
Certain instruments in which an Underlying PIMCO Fund may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on an Underlying PIMCO Fund or on certain instruments in which an Underlying PIMCO Fund invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of an Underlying PIMCO Fund's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by an Underlying PIMCO Fund or a reduction in the effectiveness of related Underlying PIMCO Fund transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of an Underlying PIMCO Fund that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to an Underlying PIMCO Fund.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

April 30, 2021 | PROSPECTUS  19

PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
PIMCO has engaged Research Affiliates, a California limited liability company (“Research Affiliates”), to serve as the asset allocation sub-adviser to the PIMCO All Asset Portfolio. Research Affiliates was organized in 2002 and is located at 620 Newport Center Drive, Suite 900, Newport Beach, CA 92660. As asset allocation sub-adviser for this Portfolio, Research Affiliates is responsible for recommending how the assets of the Portfolio are allocated and reallocated from time to time among the Underlying PIMCO Funds.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.425% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.175% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract and asset allocation sub-advisory agreement is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) . PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.

20  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Fund of Funds Fees
The Portfolio is permitted to invest in Underlying PIMCO Funds, which, for the Portfolio, is defined to include the least expensive class of shares of any actively managed or smart beta funds (including mutual funds or exchange-traded funds) of PIMCO Funds, PIMCO ETF Trust or PIMCO Equity Series, each an affiliated open-end investment company, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. Shares of the PIMCO All Asset: Multi-Real Fund, PIMCO All Asset: Multi-RAE PLUS Fund and PIMCO All Asset: Multi-Short PLUS Fund (the “PAPS All Asset Funds”) may be purchased only by the Portfolio, as well as by the PIMCO All Asset Fund and PIMCO All Asset All Authority Fund, each a series of PIMCO Funds, an affiliated investment company. 
The Portfolio pays advisory fees directly to PIMCO at an annual rate of 0.175% based on the average daily net assets attributable in the aggregate to the Portfolio’s Institutional Class shares. The Portfolio pays supervisory and administrative fees directly to PIMCO at an annual rate of 0.25% based on the average daily net assets attributable in the aggregate to the Portfolio’s Institutional Class shares. The Portfolio also indirectly pays its proportionate share of the advisory, supervisory and administrative and management fees charged by PIMCO to the Underlying PIMCO Funds and, to the extent not included among the Underlying PIMCO Funds, funds of PIMCO ETF Trust in which the Portfolio invests (collectively, “Underlying PIMCO Fund Fees”).
PIMCO has contractually agreed, through May 1, 2022, to waive the Portfolio’s advisory fee to the extent that the Underlying PIMCO Fund Fees exceed 0.64% of the total assets invested in Underlying PIMCO Funds. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the advisory fee waived as set forth above (the “Asset Allocation Reimbursement Amount”) during the previous thirty-six months from the time of waiver, provided that such amount paid to PIMCO will not: 1) together with any Underlying PIMCO Fund Fees exceed, for such month, the applicable expense limit; 2) exceed the total Asset Allocation Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
The Acquired Fund Fees and Expenses shown in the Annual Portfolio Operating Expenses table for the Portfolio may be higher than the Underlying PIMCO Fund Fees used for purposes of the Expense Reduction shown in that table due to differences in the methods of calculation. The Acquired Fund Fees and Expenses, as required to be shown in the Annual Portfolio Operating Expenses table, are calculated using the total operating expenses for each Underlying PIMCO Fund over the Portfolio’s average net assets. The Underlying PIMCO Fund Fees that are used for purposes of implementing the expense reduction described above are calculated using the advisory and supervisory and administrative fees for each Underlying PIMCO Fund over the total assets invested in Underlying PIMCO Funds. Thus, the Acquired Fund Fees and Expenses listed in the Annual Portfolio Operating Expenses table will typically be higher than the Underlying PIMCO Fund Fees used to calculate the Expense Reduction when the Portfolio employs leverage as an investment strategy.
The expenses associated with investing in a fund of funds are generally higher than those for mutual funds that do not invest in other funds. The cost of investing in the Portfolio will generally be higher than the cost of investing in a portfolio that invests directly in individual stocks and bonds. By investing in the Portfolio, an investor may indirectly bear a portion of the fees and expenses charged by Underlying PIMCO Funds, to the extent such fees and expenses are not waived or reimbursed pursuant to applicable waiver and reimbursement agreements, in addition to the Portfolio’s direct fees and expenses. In addition, the use of a fund of funds structure could affect the timing, amount and character of distributions to shareholders and may therefore increase the amount of taxes payable by shareholders. The Portfolio invests in the least expensive class of shares of the Underlying PIMCO Funds, which are not subject to any sales charges or distribution (12b-1) fees.
The following table summarizes the annual expenses borne by Institutional Class or Class M shareholders of the Underlying PIMCO Funds (or, in the case of the PAPS All Asset Funds and those operating as exchange-traded funds, the Underlying PIMCO Fund shareholders). Because the Portfolio invests in the least expensive class of shares of the Underlying PIMCO Funds, shareholders of the Portfolio would indirectly bear a proportionate share of these expenses, depending upon how the Portfolio’s assets are allocated from time to time among the Underlying PIMCO Funds.
For a complete description of an Underlying PIMCO Fund, please see the Underlying PIMCO Fund’s Institutional Class or Class M prospectus or offering memorandum, as applicable. For a summary description of the Underlying PIMCO Funds, please see the “Descriptions of the Underlying PIMCO Funds” section in this prospectus.
Annual Underlying PIMCO Fund Expenses
(Based on the average daily net assets attributable to an Underlying PIMCO Fund’s Institutional Class shares (or Class M shares in the case of the PIMCO Government Money Market Fund , or the Fund in the case of the PAPS All Asset Funds and exchange-traded funds of the PIMCO ETF Trust or PIMCO Equity Series)).)).
Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO Active Bond Exchange-Traded Fund
0.55%
0.02%
0.57%
PIMCO All Asset: Multi-RAE PLUS Fund
0.89%
0.00%
0.89%

April 30, 2021 | PROSPECTUS  21

PIMCO Variable Insurance Trust

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO All Asset: Multi-Real Fund
0.74%
0.12%
0.86%(3)
PIMCO All Asset: Multi-Short PLUS Fund
0.74%
0.02%
0.76%(3)
PIMCO California Intermediate Municipal Bond Fund
0.445%
0.00%
0.445%
PIMCO California Municipal Bond Fund
0.44%
0.02%
0.46%
PIMCO California Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Climate Bond Fund
0.50%
0.00%
0.50%
PIMCO CommoditiesPLUS® Strategy Fund
0.74%
0.27%
1.01%(4)
PIMCO CommodityRealReturn Strategy Fund®
0.74%
0.76%
1.50%(5)
PIMCO Credit Opportunities Bond Fund
0.90%
0.02%
0.92%
PIMCO Diversified Income Fund
0.75%
0.04%
0.79%
PIMCO Dividend and Income Fund
0.75%
0.05%
0.80%(6)
PIMCO Dynamic Bond Fund
0.80%
0.05%
0.85%
PIMCO Emerging Markets Bond Fund
0.83%
0.05%
0.88%
PIMCO Emerging Markets Corporate Bond Fund
0.90%
0.12%
1.02%
PIMCO Emerging Markets Currency and Short-Term Investments Fund
0.85%
0.03%
0.88%
PIMCO Emerging Markets Local Currency and Bond Fund
0.90%
0.80%
1.70%
PIMCO Enhanced Low Duration Active Exchange-Traded Fund
0.46%
0.10%
0.56%
PIMCO Enhanced Short Maturity Active ESG Exchange-Traded Fund
0.36%
0.03%
0.39%(7)
PIMCO Enhanced Short Maturity Active Exchange-Traded Fund
0.35%
0.02%
0.37%
PIMCO ESG Income Fund
0.50%
0.07%
0.57%(8)
PIMCO Extended Duration Fund
0.50%
1.21%
1.71%
PIMCO Global Advantage® Strategy Bond Fund
0.65%
0.21%
0.86%
PIMCO Global Bond Opportunities Fund (U.S. Dollar-Hedged)
0.55%
0.04%
0.59%
PIMCO Global Bond Opportunities Fund (Unhedged)
0.55%
0.12%
0.67%
PIMCO GNMA and Government Securities Fund
0.50%
0.33%
0.83%
PIMCO Government Money Market Fund
0.18%
0.00%
0.18%(9)
PIMCO High Yield Fund
0.55%
0.02%
0.57%
PIMCO High Yield Municipal Bond Fund
0.55%
0.08%
0.63%
PIMCO High Yield Spectrum Fund
0.60%
0.02%
0.62%
PIMCO Income Fund
0.50%
0.59%
1.09%
PIMCO Intermediate Municipal Bond Active Exchange-Traded Fund
0.35%
0.00%
0.35%
PIMCO International Bond Fund (U.S. Dollar-Hedged)
0.50%
0.10%
0.60%
PIMCO International Bond Fund (Unhedged)
0.50%
0.13%
0.63%
PIMCO Investment Grade Credit Bond Fund
0.50%
0.35%
0.85%
PIMCO Long Duration Total Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term Credit Bond Fund
0.55%
0.29%
0.84%
PIMCO Long-Term Real Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term U.S. Government Fund
0.475%
1.38%
1.855%
PIMCO Low Duration Credit Fund(10)
0.70%
0.05%
0.75%
PIMCO Low Duration ESG Fund
0.50%
0.08%
0.58%
PIMCO Low Duration Fund
0.46%
0.41%
0.87%
PIMCO Low Duration Fund II
0.50%
0.03%
0.53%
PIMCO Low Duration Income Fund
0.50%
0.05%
0.55%
PIMCO Moderate Duration Fund
0.46%
0.15%
0.61%
PIMCO Mortgage Opportunities and Bond Fund
0.60%
1.22%
1.82%
PIMCO Mortgage-Backed Securities Fund
0.50%
0.25%
0.75%
PIMCO Municipal Bond Fund
0.44%
0.07%
0.51%
PIMCO National Intermediate Municipal Bond Fund
0.45%
0.00%
0.45%
PIMCO New York Municipal Bond Fund
0.445%
0.05%
0.495%
PIMCO Preferred and Capital Securities Fund
0.79%
0.09%
0.88%(11)
PIMCO RAE Emerging Markets Fund
0.75%
0.02%
0.77%(6)
PIMCO RAE Fundamental Advantage PLUS Fund
0.89%
0.07%
0.96%

22  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO RAE International Fund
0.50%
0.02%
0.52%(6)
PIMCO RAE PLUS EMG Fund
1.10%
0.21%
1.31%
PIMCO RAE PLUS Fund
0.79%
0.08%
0.87%
PIMCO RAE PLUS International Fund
0.82%
0.05%
0.87%
PIMCO RAE PLUS Small Fund
0.84%
0.09%
0.93%
PIMCO RAE US Fund
0.40%
0.02%
0.42%(6)
PIMCO RAE US Small Fund
0.50%
0.04%
0.54%
PIMCO RAE Worldwide Long/Short PLUS Fund
1.19%
0.09%
1.28%
PIMCO RAFI Dynamic Multi-Factor Emerging Markets Equity ETF
0.49%
0.01%
0.50%(12)
PIMCO RAFI Dynamic Multi-Factor International Equity ETF
0.39%
0.02%
0.41%(12)
PIMCO RAFI Dynamic Multi-Factor U.S. Equity ETF
0.29%
0.02%
0.31%(12)
PIMCO RAFI ESG U.S. ETF
0.29%
0.01%
0.30%
PIMCO Real Return Fund
0.45%
0.08%
0.53%
PIMCO RealEstateRealReturn Strategy Fund
0.74%
1.36%
2.10%
PIMCO Short Asset Investment Fund
0.34%
0.02%
0.36%
PIMCO Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Short Term Municipal Bond Active Exchange-Traded Fund
0.35%
0.00%
0.35%
PIMCO Short-Term Fund
0.45%
0.10%
0.55%
PIMCO StocksPLUS® Absolute Return Fund
0.64%
0.08%
0.72%
PIMCO StocksPLUS® Fund
0.50%
0.06%
0.56%
PIMCO StocksPLUS® International Fund (U.S. Dollar-Hedged)
0.75%
0.25%
1.00%
PIMCO StocksPLUS® International Fund (Unhedged)
0.64%
0.38%
1.02%
PIMCO StocksPLUS® Long Duration Fund
0.59%
0.42%
1.01%
PIMCO StocksPLUS® Short Fund
0.64%
0.45%
1.09%
PIMCO StocksPLUS® Small Fund
0.69%
0.06%
0.75%
PIMCO Strategic Bond Fund
0.55%
0.02%
0.57%(13)
PIMCO Total Return ESG Fund
0.50%
0.46%
0.96%
PIMCO Total Return Fund
0.46%
0.24%
0.70%
PIMCO Total Return Fund II
0.50%
0.26%
0.76%
PIMCO Total Return Fund IV
0.50%
0.30%
0.80%
PIMCO TRENDS Managed Futures Strategy Fund
1.40%
0.29%
1.69%(14)
1
“Management Fees” reflects an advisory fee and a supervisory and administrative fee payable by an Underlying PIMCO Fund to PIMCO.
2
Other Expenses include expenses such as organizational expenses, interest expense, taxes, governmental fees, pro rata Trustees' fees and acquired fund fees and expenses attributable to the Institutional Class or Class M shares or the Fund in the case of exchange-traded funds of the PIMCO ETF Trust or PIMCO Equity Series.
3
PIMCO has contractually agreed, through July 31, 2021, to waive a portion of the Fund’s supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Funds at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided certain conditions are met.
4
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund III Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
5
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund I Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
6
PIMCO has contractually agreed, through October 31, 2021, to waive a portion of the Fund's supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund's organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Equity Series at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.

April 30, 2021 | PROSPECTUS  23

PIMCO Variable Insurance Trust

7
PIMCO has contractually agreed, through October 31, 2022, to reduce its management fee by 0.12% of the average daily net assets of the Fund. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO ETF Trust at least 30 days prior to the end of the then current term. In any month in which the investment management agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the management fee waived as set forth above during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
8
PIMCO has contractually agreed, through July 31, 2022, to waive a portion of the Fund’s supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
9
To maintain certain net yields for the Fund, PIMCO or its affiliates may temporarily and voluntarily waive, reduce or reimburse all or any portion of the Fund's fees and expenses.
10
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund.
11
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Capital Securities Fund (Cayman) Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
12
PIMCO has contractually agreed, through October 31, 2021, to waive a portion of the Fund’s management fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Equity Series at least 30 days prior to the end of the then current term. In any month in which the investment management agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the management fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
13
PIMCO has contractually agreed, through July 31, 2021, to reduce its supervisory and administrative fee for each share class of the Fund by 0.05% of the average daily net assets attributable to the applicable class of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years from the date of waiver.
14
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund VIII, Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO All Asset
Robert D. Arnott
4/03*
Chairman and Founder, Research Affiliates, since July 2002. Previously, Mr. Arnott was
Chairman of First Quadrant, L.P. until April 2004. He first joined First Quadrant in April
1998.
PIMCO All Asset
Christopher J. Brightman
11/16
Chief Investment Officer, Research Affiliates, since April 2014. Previously at Research
Affiliates, Mr. Brightman served as a Managing Director and Head of Investment
Management. Prior to joining Research Affiliates in 2010, Mr. Brightman was chief
executive officer of the University of Virginia Investment Management Company.
*
Inception of the Portfolio.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.

24  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

April 30, 2021 | PROSPECTUS  25

PIMCO Variable Insurance Trust

Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

26  Prospectus | PIMCO Variable Insurance Trust

Prospectus

From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Underlying PIMCO Funds’ investment strategies may expose such Underlying PIMCO Funds to risks associated with market timing activities. For example, since some Underlying PIMCO Funds may invest in non-U.S. securities, they may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of an Underlying PIMCO Fund’s non-U.S. portfolio securities and the determination of the Underlying PIMCO Fund’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling fund shares at a price that does not reflect their true value. A similar risk exists for an Underlying PIMCO Fund’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
Except as identified below, to discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders (“Market Timing Policy”). Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders. In addition, purchases and sales by the Portfolio in certain Underlying PIMCO Funds may be exempt from certain limitations under the Market Timing Policy in order to allow the Portfolio to manage its cash flows and reallocate portfolio investments in the Underlying PIMCO Funds according to its allocation targets.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.

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How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio and Underlying PIMCO Fund shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or an Underlying PIMCO Fund or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
The assets of the Portfolio consist of shares of the Underlying PIMCO Funds, which are valued at their respective NAVs at the time of valuation of the Portfolio’s shares. For purposes of calculating the NAV of the Underlying PIMCO Funds, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity
options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of an Underlying PIMCO Fund’s assets that are invested in one or more open-end management investment companies, (other than exchange-traded funds), the Underlying PIMCO Fund’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of an Underlying PIMCO Fund’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or

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denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio invests in Underlying PIMCO Funds that hold foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Trustees or persons acting at their direction. The Trustees has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO.
Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of an Underlying PIMCO Fund’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When an Underlying PIMCO Fund uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board of Trustees or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s and Underlying PIMCO Funds’ NAVs that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Underlying PIMCO Fund could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by an Underlying PIMCO Fund may differ from the value that would be realized if the securities were sold. An Underlying PIMCO Fund’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.The Portfolio may invest in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund. One of the requirements for favorable tax treatment as a regulated investment company under the Code is that each Underlying PIMCO Fund derive at least 90% of its gross income from certain qualifying sources of income. The IRS has issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. As such, each Underlying PIMCO Fund’s ability to utilize commodity-linked swaps as part of its investment strategy is limited to a maximum of 10 percent of its gross income.

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Prospectus

However, in a subsequent revenue ruling, the IRS provides that income from alternative investment instruments (such as certain commodity index-linked notes) that create commodity exposure may be considered qualifying income under the Code. The IRS has also issued a private letter ruling to the Underlying PIMCO Funds in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued another private letter ruling to each Underlying PIMCO Fund in which the IRS specifically concluded that income derived from the Underlying PIMCO Fund’s investment in its Subsidiary will also constitute qualifying income to the Underlying PIMCO Fund, even if the Subsidiary itself owns commodity linked swaps. Each Underlying PIMCO Fund will continue to seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in its Subsidiary.
Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if an Underlying PIMCO Fund‘s income from an investment in the subsidiary is derived with respect to the Underlying PIMCO Fund’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the 1940 Act. In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings. There can be no assurance that the IRS will not change its position with respect to some or all of these conclusions or that future legislation will not adversely impact the tax treatment of each Underlying PIMCO Fund’s commodity-linked investments. If the IRS were to change or reverse its position, or if future legislation adversely affected the tax treatment of the commodity-linked investments of each Underlying PIMCO Fund, there would likely be a significant adverse impact on the Underlying PIMCO Fund, including the possibility of failing to qualify as a regulated investment company. If an Underlying PIMCO Fund did not qualify as a regulated investment company for any taxable year, its taxable income would be subject to tax at the Underlying PIMCO Fund level at regular corporate tax rates (without reduction for distributions to shareholders) and to a further tax at the shareholder level when such income is distributed.
Furthermore, the tax treatment of commodity-linked notes, other commodity-linked derivatives, and an Underlying PIMCO Fund’s investments in its Subsidiary may otherwise be adversely affected by future legislation, court decisions, Treasury Regulations and/or guidance issued by the IRS. Such developments could affect the character, timing and/or amount of the Underlying PIMCO Fund’s taxable income or any distributions made by the Underlying PIMCO Fund or result in the inability of the Underlying PIMCO Fund to operate as described in its prospectus.
A Note on the PIMCO CommodityRealReturn Strategy Fund®, an Underlying PIMCO Fund.Periodic adjustments for inflation to the principal amount of an inflation-indexed bond may give rise to original issue discount, which will be includable in the Underlying PIMCO Fund’s gross income. Due to original issue
discount, the Underlying PIMCO Fund may be required to make annual distributions to shareholders that exceed the cash received, which may cause the Underlying PIMCO Fund to liquidate certain investments when it is not advantageous to do so. Also, if the principal value of an inflation-indexed bond is adjusted downward due to deflation, amounts previously distributed in the taxable year may be characterized in some circumstances as a return of capital.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
The Portfolio invests substantially all of its assets in shares of the Underlying PIMCO Funds, and as such (unless otherwise noted) does not invest directly in the securities described below. The Underlying PIMCO Funds, however, may invest in such securities. Because the value of an investment in the Portfolio is directly related to the investment performance of the Underlying PIMCO Funds in which it invests, the risks of investing in the Portfolio are closely related to the risks associated with the Underlying PIMCO Funds and their investments in the securities described below. Please see the “Descriptions of the Underlying PIMCO Funds.”
This section provides additional information about some of the principal investments and related risks of the Portfolio and the Underlying PIMCO Funds described under the “Portfolio Summary,” “Description of Principal Risks” and “Descriptions of the Underlying PIMCO Funds.” It also describes characteristics and risks of additional securities and investment techniques that may be used by the Underlying PIMCO Funds from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Underlying PIMCO Funds. As with any mutual fund, investors in the Underlying PIMCO Funds rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Underlying PIMCO Funds.
Because the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, may each invest a portion of its assets in its respective Subsidiary, each of which may hold some of the investments described in this prospectus, each Underlying PIMCO Fund, and to the extent the Portfolio invests in each Underlying PIMCO Fund, the Portfolio, may be indirectly exposed to the

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risks associated with those investments. With respect to its investments, each Subsidiary will generally be subject to the same fundamental, non-fundamental and certain other investment restrictions as the respective Underlying PIMCO Fund; however, each Subsidiary (unlike the Underlying PIMCO Fund) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. Each Underlying PIMCO Fund and each Subsidiary may test for compliance with certain investment restrictions on a consolidated basis, except that with respect to its investments in certain securities that may involve leverage, the Subsidiary will comply with asset segregation or “earmarking” requirements to the same extent as its respective Underlying PIMCO Fund.
Investors should be aware that the investments made by a Portfolio and the results achieved by a Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to a Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact a Portfolio’s portfolio management. For example, a Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause Portfolios to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase a Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause a Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect a Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also
increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
Most of the Underlying PIMCO Funds seek maximum total return. The total return sought by an Underlying PIMCO Fund consists of both income earned on the Underlying PIMCO Fund’s investments and capital appreciation, if any, arising from increases in the market value of the Underlying PIMCO Fund’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation or improving credit fundamentals for a particular market sector or security.
In selecting securities for an Underlying PIMCO Fund, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Underlying PIMCO Fund’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);

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corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition,

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imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Underlying PIMCO Fund to sell its bonds at attractive pries or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolios may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Underlying PIMCO Funds may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Underlying PIMCO Funds may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Underlying PIMCO Funds is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Underlying PIMCO Funds may subject the Underlying PIMCO Funds to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if an Underlying PIMCO Fund sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
Certain Underlying PIMCO Funds may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing
interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that an Underlying PIMCO Fund investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose an Underlying PIMCO Fund to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the

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time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The value of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk.Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect an Underlying PIMCO Fund’s returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Underlying PIMCO Funds may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk.Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Underlying PIMCO Funds to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on an Underlying PIMCO Fund’s yield to maturity from these securities. Certain Underlying PIMCO Funds may invest up to 5% of their total assets in any combination of mortgage-related or other asset backed IO, PO or inverse floater securities.
An Underlying PIMCO Fund may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties.
Loan Participations and Assignments
Certain Underlying PIMCO Funds may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If an Underlying PIMCO Fund purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
An Underlying PIMCO Fund may be subject to the risk that the returns of the Underlying PIMCO Fund will decline during periods of falling interest rates because the Underlying PIMCO Fund may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Underlying PIMCO Fund’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Underlying PIMCO Fund to invest in lower-yielding securities. An Underlying PIMCO Fund also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Underlying PIMCO Fund’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by an Underlying PIMCO Fund from its investments is likely to have an adverse effect on the Underlying PIMCO Fund’s NAV, yield and total return.
Focused Investment
To the extent that an Underlying PIMCO Fund focuses its investments in a particular sector, the Underlying PIMCO Fund may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, an Underlying PIMCO Fund may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Underlying PIMCO Fund to greater risk. An Underlying

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PIMCO Fund also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. Certain Underlying PIMCO Funds may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case an Underlying PIMCO Fund may lose its entire investment. The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which an Underlying PIMCO Fund may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate
instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. Each Underlying PIMCO Fund may invest in floating rate debt instruments (“floaters”) and certain Underlying PIMCO Funds may engage in credit spread trades. . A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Certain Underlying PIMCO Funds may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. Underlying PIMCO Funds that may invest in these securities may invest up to 5% of their total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, certain Underlying PIMCO Funds may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of

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municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Volatility
Volatility measures the variability in the price of an investment over time. A higher volatility level signifies an investment’s value may fluctuate over a larger range within a short period of time, either up or down. A lower volatility level means an investment’s value is more likely to change within a narrower range, or less frequently, over time. The more volatile the portfolio holdings of the Portfolio, the less predictable the returns for the Portfolio. Higher volatility levels may indicate heightened risk of losses.
PIMCO’s use of investments in seeking to manage the Portfolio‘s volatility will be consistent with the Portfolio’s asset allocation guidelines. Although asset allocation cannot eliminate investment risk or losses, it may provide opportunities to manage a Portfolio’s volatility relative to a Portfolio’s target annualized volatility level.
Event-Linked Exposure
Certain Underlying PIMCO Funds may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, an Underlying PIMCO Fund may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposures may also expose an Underlying PIMCO Fund to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposures may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
Certain Underlying PIMCO Funds may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. An Underlying PIMCO Fund may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Underlying PIMCO Fund’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. An Underlying PIMCO Fund may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior

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securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, an Underlying PIMCO Fund may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for an Underlying PIMCO Fund.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time. In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to an Underlying PIMCO Fund as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, an Underlying PIMCO Fund may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, certain Underlying PIMCO Funds may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by an Underlying PIMCO Fund at any given time upon sale thereof, an Underlying PIMCO Fund may determine to hold such securities in its portfolio.
While certain Underlying PIMCO Funds will generally invest in equity derivatives and will not normally invest directly in equity securities, each such Underlying PIMCO Fund may invest without limit directly in equity securities, including common stocks, preferred securities and convertible securities. In addition, the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, each an Underlying PIMCO Fund, may invest in equity securities of issuers in commodity-related industries, and the PIMCO RealEstateRealReturn Strategy Fund, an Underlying PIMCO Fund, may invest in REITs and equity securities of issuers in real estate-related industries. When investing directly in equity securities, an Underlying PIMCO Fund will not be limited to only those equity securities with any particular weighting in such Underlying PIMCO Fund’s respective benchmark index, if any. Generally, the Underlying PIMCO Funds will consider investing directly in equity securities when derivatives on the underlying securities appear to be overvalued.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by an Underlying PIMCO Fund may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
Certain Underlying PIMCO Funds may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instrument is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws

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of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, if the issuer of such money market instrument is organized under the laws of a non-U.S. country, or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Underlying PIMCO Funds that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruption, the possibility of security suspensions and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries’ financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in or uncertainty concerning,
foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers' financial reporting.
Certain of the Underlying PIMCO Funds also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.Certain Underlying PIMCO Funds may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries within the limitations, if any, set forth in each Underlying PIMCO Fund’s prospectus. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors, and the order in which they are applied may change in the discretion of PIMCO. The current factors listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency

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of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, an Underlying PIMCO Fund emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by an Underlying PIMCO Fund. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause an Underlying PIMCO Fund to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates
also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which an Underlying PIMCO Fund’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Underlying PIMCO Fund.
Foreign Currency Transactions.Underlying PIMCO Funds that invest in securities denominated in foreign (non-U.S.) currencies may engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Underlying PIMCO Fund’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Underlying PIMCO Fund is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Underlying PIMCO Fund’s ability to enter into foreign currency transactions, force the Underlying PIMCO Fund to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Underlying PIMCO Fund, any of which may result in a loss to the Underlying PIMCO Fund. A contract to sell a foreign currency would limit any potential gain which might be realized if the value of the hedged currency increases. An Underlying PIMCO Fund may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that an Underlying PIMCO Fund will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for an Underlying PIMCO Fund to benefit from favorable fluctuations in relevant foreign currencies. An Underlying PIMCO Fund may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Underlying PIMCO Fund will segregate or “earmark” assets determined to be liquid by PIMCO in accordance with the procedures established by the Board of Trustees (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.

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Prospectus

Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of an Underlying PIMCO Fund’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, an Underlying PIMCO Fund’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. An Underlying PIMCO Fund may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if an Underlying PIMCO Fund earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Underlying PIMCO Fund’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio and each Underlying PIMCO Fund may enter into repurchase agreements, in which the Portfolio or the Underlying PIMCO Fund purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s or the Underlying PIMCO Fund’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio or the Underlying PIMCO Fund will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
Each Underlying PIMCO Fund may enter into reverse repurchase agreements and dollar rolls, subject to the Underlying PIMCO Fund’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by an Underlying PIMCO Fund and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Underlying PIMCO Fund but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, an Underlying PIMCO Fund will segregate or “earmark”
assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for an Underlying PIMCO Fund.
The Portfolio and Underlying PIMCO Funds may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio or Underlying PIMCO Fund may borrow money from banks for any purpose in an amount up to 1/3 of the Portfolio’s or Underlying PIMCO Fund’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio or Underlying PIMCO Fund may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s or Underlying PIMCO Fund’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
Certain Underlying PIMCO Funds may, but are not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). An Underlying PIMCO Fund may invest some or all of its assets in derivative instruments, subject to the Underlying PIMCO Fund’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by an Underlying PIMCO Fund will succeed. A description of these and other derivative instruments that the Underlying PIMCO Funds may use are described under “Investment Objectives and Policies” in the SAI.
An Underlying PIMCO Fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on an Underlying PIMCO Fund. For example, a small investment in a derivative instrument may have a significant impact on an Underlying PIMCO Fund’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. An Underlying PIMCO Fund may engage in such transactions regardless of whether the Underlying PIMCO Fund owns the asset, instrument or components of the index underlying the derivative instrument. An Underlying PIMCO Fund may invest a significant portion of its assets in these types of instruments. If it does, the Underlying PIMCO Fund’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in

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“Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Underlying PIMCO Funds.
CPI Swap. A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk. Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk. The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if an Underlying PIMCO Fund does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk. Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk. Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When an Underlying PIMCO Fund uses derivatives for leverage, investments in that Underlying PIMCO Fund will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Underlying PIMCO Fund will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability. Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain an Underlying PIMCO Fund’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that an Underlying PIMCO Fund will engage in derivatives transactions at any time or from time to time. An Underlying PIMCO Fund’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk. In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, many of the Underlying PIMCO Funds seek to achieve their investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of these Underlying PIMCO Funds are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent an Underlying PIMCO Fund, or derivatives or other strategies used by the Underlying PIMCO Fund, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Underlying PIMCO Fund and the determination of the NAV value of Underlying PIMCO Fund shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Underlying PIMCO Fund invests; (iv) a fund having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of a fund (due to share purchases or redemptions, for example), potentially resulting in the Underlying PIMCO Fund being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Underlying PIMCO Fund’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks. Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to an Underlying PIMCO Fund’s interest. If a portfolio manager incorrectly forecasts the values of

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Prospectus

securities, currencies or interest rates or other economic factors in using derivatives for an Underlying PIMCO Fund, the Underlying PIMCO Fund might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Underlying PIMCO Fund investments. An Underlying PIMCO Fund may also have to buy or sell a security at a disadvantageous time or price because the Underlying PIMCO Fund is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Underlying PIMCO Fund’s derivative transactions, or impede the employment of the Underlying PIMCO Fund’s derivatives strategies, or adversely affect the Underlying PIMCO Fund’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to an Underlying PIMCO Fund. In addition, an Underlying PIMCO Fund’s use of derivatives may cause the Underlying PIMCO Fund to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Underlying PIMCO Fund had not used such instruments.
A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.The Portfolio may invest in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund. In light of releveant IRS guidance, as discussed above under “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” will seek to gain exposure to the commodity markets primarily through investments in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices, and through investments in its respective Subsidiary (as discussed below). The Underlying PIMCO Funds may also invest in commodity-linked notes with principal and/or coupon payments linked to the value of particular commodities or commodity futures contracts, or a subset of commodities and commodities futures contracts.
These notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in
response to changes in the underlying commodity, commodity futures contract, subset of commodities, subset of commodities futures contracts or commodity index.
These notes expose the Underlying PIMCO Funds economically to movements in commodity prices. These notes also are subject to risks, such as credit, market and interest rate risks, that in general affect the values of debt securities. In addition, these notes are often leveraged, increasing the volatility of each note’s market value relative to changes in the underlying commodity, commodity futures contract or commodity index. Therefore, at the maturity of the note, the Underlying PIMCO Funds may receive more or less principal than it originally invested. The Underlying PIMCO Funds might receive interest payments on the note that are more or less than the stated coupon interest payments.
The Underlying PIMCO Funds may also invest in other commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures. The value of a commodity-linked derivative investment generally is based upon the price movements of a physical commodity (such as energy, mineral, or agricultural products), a commodity futures contract, a subset of commodities, a subset of commodities futures contracts or commodity index, or other economic variable based upon changes in the value of commodities or the commodities markets.
Options transactions may be effected on exchanges or in the OTC market. When OTC options are purchased, an Underlying PIMCO Fund’s portfolio bears the risk that the counterparty that wrote the option will be unable or unwilling to perform its obligations under the option contract. Options may also be illiquid and, in such cases, an Underlying PIMCO Fund may have difficulty closing out its position. OTC options also may include options on baskets of specific securities.
Many swap transactions are privately negotiated agreements between a fund and a counterparty to exchange or swap investment cash flows or assets at specified intervals in the future. The obligations may extend beyond one year. There is often no central exchange for swap transactions and therefore they can be less liquid investments than exchange-traded instruments. The Dodd-Frank Act and related regulatory developments require the clearing and exchange-trading of certain standardized OTC derivative instruments that the CFTC and SEC have defined as “swaps.” The CFTC has implemented mandatory exchange-trading and clearing requirements under the Dodd-Frank Act and the CFTC continues to approve contracts for central clearing. Uncleared swaps are subject to margin requirements that are being implemented on a phased-in basis. The investment adviser will continue to monitor these developments, particularly to the extent regulatory changes affect an Underlying PIMCO Fund’s ability to enter into swap agreements.
As described below under “Characteristics and Risks of Securities and Investment Techniques-Investments in a Wholly-Owned Subsidiary,” the Underlying PIMCO Funds may gain exposure to commodity markets by investing in their respective Subsidiaries. It is expected that each such Subsidiary will invest primarily in commodity-linked derivative

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instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments.
The IRS issued a revenue ruling that limits the extent to which the Underlying PIMCO Funds may invest directly in commodity-linked swaps or certain other commodity-linked derivatives. The Subsidiaries, on the other hand, may invest in these commodity-linked derivatives generally without limitation. See “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” above for further information.
Investments in a Wholly Owned Subsidiary
Investments in the Subsidiaries by the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, are expected to provide the Underlying PIMCO Funds with exposure to the commodity markets within the limitations of Subchapter M of the Code and recent IRS revenue rulings, as discussed above under “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.”
It is expected that each Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation indexed securities and other Fixed Income Instruments. Although the Underlying PIMCO Funds may enter into these commodity-linked derivative instruments directly, the Underlying PIMCO Funds will likely gain exposure to these derivative instruments indirectly by investing in the their respective Subsidiaries. To the extent that PIMCO believes that these commodity-linked derivative instruments are better suited to provide exposure to the commodities market than commodity index-linked notes, each Underlying PIMCO Fund’s investment in its respective Subsidiary will likely increase. Each Subsidiary will also invest in inflation-indexed securities and/or other Fixed Income Instruments, which are intended to serve as margin or collateral for the Subsidiary’s derivatives position, common and preferred securities as well as convertible securities of issuers in commodity-related industries, collateralized debt obligations, event-linked bonds and event-linked swaps. To the extent that an Underlying PIMCO Fund invests in its respective Subsidiary, it may be subject to the risks associated with those derivative instruments and other securities, which are discussed elsewhere in this prospectus.
While each Subsidiary may be considered similar to an investment company, it is not registered under the 1940 Act and, unless otherwise noted in each Underlying PIMCO Fund’s prospectus, is not subject to all of the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of an Underlying PIMCO Fund and/or a Subsidiary to operate as described in this prospectus and the SAI and could adversely affect an Underlying PIMCO Fund as well as the Portfolio (to the extent the
Portfolio invests in an Underlying PIMCO Fund). Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of an Underlying PIMCO Fund and/or a Subsidiary and result in the Underlying PIMCO Fund underperforming its benchmark index(es).
Real Estate Investment Trusts (REITs)
Certain Underlying PIMCO Funds may invest in REITs. REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
Certain Underlying PIMCO Funds may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in

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Prospectus

the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
Certain Underlying PIMCO Funds may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring an Underlying PIMCO Fund to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that an Underlying PIMCO Fund is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
Each Underlying PIMCO Fund may purchase or sell securities which it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Underlying PIMCO Fund’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Underlying PIMCO Fund’s overall investment exposure. Typically, no income accrues on securities that an Underlying PIMCO Fund has committed to purchase prior to the time delivery of the securities is made, although the Underlying PIMCO Fund may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio invests substantially all of its assets in other investment companies. The Portfolio’s investment in a particular Underlying PIMCO Fund normally will not exceed 50% of its total assets. An Underlying PIMCO Fund may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio and each Underlying PIMCO Fund may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Each Underlying PIMCO Fund may invest in securities of other investment companies, such as closed-end management investment companies including exchange-traded funds, or in pooled accounts or other investment vehicles which to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The limitation described in the foregoing sentence shall not apply to the investments of the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund in the Subsidiaries. As a shareholder of an investment company or other pooled vehicle, the Portfolio or Underlying PIMCO Funds may indirectly bear service and other fees which are in addition to the fees the Portfolio or Underlying PIMCO Funds pays its service providers.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, each Underlying PIMCO Fund may, in the future and the rules and regulations thereunder and any exemptive relief thereform, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Underlying PIMCO Fund.
Small-Cap and Mid-Cap Companies
Certain Underlying PIMCO Funds may invest in equity securities of small-capitalization and mid-capitalization companies, a small-cap company generally considered to be a company with a market

April 30, 2021 | PROSPECTUS  45

PIMCO Variable Insurance Trust

capitalization of up to $1.5 billion and a mid-cap company generally considered to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Underlying PIMCO Fund’s investments in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
Each Underlying PIMCO Fund may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose an Underlying PIMCO Fund to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Underlying PIMCO Fund. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”), the Underlying PIMCO Fund must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that an Underlying PIMCO Fund contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. An Underlying PIMCO Fund may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent an Underlying PIMCO Fund engages in short selling in foreign (non-U.S.) jurisdictions, the Underlying PIMCO Fund will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
Each Underlying PIMCO Fund may invest up to 15% of its net assets (5% of total assets in the case of the PIMCO Government Money Market Fund) (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments, and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that an Underlying PIMCO Fund reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial
paper) may be treated as liquid (i.e., classified by an Underlying PIMCO Fund in a liquidity category other than “illiquid” pursuant to the Underlying PIMCO Fund’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, each Underlying PIMCO Fund may lend its portfolio securities to brokers, dealers, and other financial institutions provided a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When an Underlying PIMCO Fund lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Underlying PIMCO Fund will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. An Underlying PIMCO Fund may pay lending fees to a party arranging the loan. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time an Underlying PIMCO Fund has held a particular security is not generally a consideration in investment decisions. A change in the securities held by an Underlying PIMCO Fund is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, an Underlying PIMCO Fund may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Underlying PIMCO Fund’s portfolio) involves correspondingly greater expenses to an Underlying PIMCO Fund, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect an Underlying PIMCO Fund’s performance. Please see the Portfolio’s “Portfolio Summary – Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio and each Underlying PIMCO Fund may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities, in attempting

46  Prospectus | PIMCO Variable Insurance Trust

Prospectus

to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio or Underlying PIMCO Fund engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s or an Underlying PIMCO Fund’s total net assets may be uninvested. In such cases, Portfolio or Underlying PIMCO Fund assets will be held in cash in the Portfolio’s or Underlying PIMCO Fund’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objectives of the Portfolio and certain Underlying PIMCO Funds are fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval. The investment objectives of certain Underlying PIMCO Funds may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio and Underlying PIMCO Fund investments listed in this prospectus will apply at the time of investment. The Portfolio and each Underlying PIMCO Fund would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. Certain Underlying PIMCO Funds have adopted a policy to invest at least 80% of their assets in investments suggested by their name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. An Underlying PIMCO Fund will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by an Underlying PIMCO Fund could receive a higher rating or a lower rating during the period in which they are held by an Underlying PIMCO Fund. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
An Underlying PIMCO Fund may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Underlying PIMCO Fund may purchase. In making ratings
determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that a portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Underlying PIMCO Fund invests in high yield and/or unrated securities, the Underlying PIMCO Fund’s success in achieving its investment objective may depend more heavily on the portfolio managers’ creditworthiness analysis than if the Underlying PIMCO Fund invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Underlying PIMCO Funds may invest in other types of securities and use a variety of investment techniques and strategies which are not described in this prospectus. These securities and techniques may subject the Underlying PIMCO Funds to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Underlying PIMCO Funds.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, sub-advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage;

April 30, 2021 | PROSPECTUS  47

PIMCO Variable Insurance Trust

reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

48  Prospectus | PIMCO Variable Insurance Trust


Descriptions of the Underlying PIMCO Funds
The Portfolio invests substantially all of its assets in some or all of the Underlying PIMCO Funds, which is defined to include the least expensive class of shares of any actively managed or smart beta funds (including mutual funds or exchange-traded funds) of PIMCO Funds, PIMCO ETF Trust or PIMCO Equity Series, each an affiliated open-end investment company, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. Shares of the PIMCO All Asset: Multi-Real Fund, PIMCO All Asset: Multi-RAE PLUS Fund and PIMCO All Asset: Multi-Short PLUS Fund (the “PAPS All Asset Funds”) may be purchased only by the Portfolio, as well as by the PIMCO All Asset Fund and PIMCO All Asset All Authority Fund, each a series of PIMCO Funds, an affiliated investment company. Because the Underlying PIMCO Funds are not offered in this prospectus, the following provides a general description of the main investments and other information about the Underlying PIMCO Funds. At the discretion of PIMCO and without shareholder approval, the Portfolio may invest in additional Underlying PIMCO Funds created in the future. For a complete description of an Underlying PIMCO Fund, please see that Fund’s Institutional Class or Class M prospectus (or Fund prospectus in the case of any exchange-traded fund of the PIMCO ETF Trust or PIMCO Equity Series, or Fund offering memorandum in the case of the PAPS All Asset Funds), which is incorporated herein by reference and is available free of charge by telephoning 1-800-927-4648.
Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Short Duration
PIMCO Low Duration Income
Short maturity fixed income instruments
0 to 3 years
Max 30% of total
assets below Baa(3)
No Limitation(4)
PIMCO Short Asset Investment
Money market instruments and short maturity
fixed income instruments
≤ 1.5 years
Baa to Aaa
0%
PIMCO Short-Term
Money market instruments and short maturity
fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below Baa
0-10% of total
assets(5)
PIMCO Low Duration
Short maturity fixed income instruments
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration II
Short maturity fixed income instruments with
quality and non-U.S. issuer restrictions
1 to 3 years
A to Aaa
0%
PIMCO Low Duration ESG
Short maturity fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration Credit(10)
Diversified portfolio of fixed income
instruments
0 to 3 years
Max 10% of total
assets below Caa
0-25% of total
assets(11)
Intermediate
Duration
PIMCO Moderate Duration
Short and intermediate maturity fixed income
instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO GNMA and Government
Securities
Short and intermediate maturity
mortgage-related fixed income securities issued
by the Government National Mortgage
Association and U.S. government securities
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa
0%
PIMCO High Yield
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(6); max
20% of total assets
Caa or below
0-20% of total
assets(5)
PIMCO High Yield Spectrum
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(7)
No Limitation(8)
PIMCO Mortgage-Backed Securities
Short and intermediate maturity
mortgage-related fixed income instruments
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa(9)
0%
PIMCO Total Return
Intermediate maturity fixed income instruments
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return II
Intermediate maturity fixed income instruments
with quality and non-U.S. issuer restrictions
+/-2 years of its
benchmark
Baa to Aaa
0%
PIMCO Total Return ESG
Intermediate maturity fixed income instruments
with prohibitions on firms engaged in socially
sensitive practices
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return IV
Intermediate maturity fixed income instruments
+/-1.5 years of its
benchmark
Baa to Aaa
0-15% of total
assets(11)
PIMCO Investment Grade Credit Bond
Investment grade fixed income securities
+/-2 years of its
benchmark
Max 15% of total
assets below Baa
0-30% of total
assets(5)

  49


Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Long Duration
PIMCO Long Duration Total Return
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Extended Duration
Long-term maturity fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO Long-Term U.S. Government
Long-term maturity fixed income securities
≥ 8 years
A to Aaa; max 25% Aa;
max 10% A
0%
PIMCO Mortgage Opportunities and
Bond
Mortgage-related assets and fixed income
instruments
(-1) to 8 years
Max 50% of total
assets below Baa(12)
0%
PIMCO Long-Term Credit Bond
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
B to Aaa; max 20% of
total assets below Baa
0-30% of total
assets(5)
Income
PIMCO ESG Income
Broad range of fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Income
Broad range of fixed income instruments
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Preferred and Capital Securities
Capital securities and preferred securities
+/-2 years of its
benchmark
No Limitation
No Limitation(4)
Inflation-Related
PIMCO Real Return
Inflation-indexed fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO Long-Term Real Return
Inflation-indexed fixed income securities
+/-4 years of its
benchmark
B to Aaa; max 20% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO CommoditiesPLUS® Strategy
Commodity-linked derivative instruments
backed by an actively managed low volatility
portfolio of fixed income instruments
≤ 1 year
Max 10% of total
assets below Baa
0-20%(4)
PIMCO CommodityRealReturn Strategy®
Commodity-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO RealEstateRealReturn Strategy
Real estate-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO All Asset: Multi-Real
Derivatives linked to real assets complemented
by a portfolio of inflation-linked securities and
other Fixed Income Instruments
≤ 10 years
B to Aaa; max 20%
below Baa(14)
0-30% of total
assets with respect
to the Fund’s
investments in
Fixed Income
Instruments(15)
Tax Exempt
PIMCO California Short Duration
Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal and California
income tax)
≤ 3 years
Caa to Aaa; max 10%
of total assets below
Baa
0%
PIMCO California Municipal Bond
Municipal securities (exempt from federal and
California income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO Short Duration Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal income tax)
≤ 3 years
Baa to Aaa
0%
PIMCO California Intermediate Municipal
Bond
Intermediate maturity municipal securities
(exempt from federal and California income
tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO National Intermediate Municipal
Bond
Municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO New York Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal and New York
income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO High Yield Municipal Bond
Intermediate to long-term maturity high yield
municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
No Limitation
0%

50  


Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
PIMCO Emerging Markets Bond
Emerging market fixed income instruments
+/- 2 years of its
benchmark
Max 15% of total
assets below B
≥ 80% of assets(16)
PIMCO Emerging Markets Currency and
Short-Term Investments
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and short-term investments
≤ 2 years
Max 15% of total
assets below B
No Limitation(17)
PIMCO International Bond
(U.S. Dollar-Hedged)
Intermediate maturity hedged non-U.S. fixed
income instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO International Bond (Unhedged)
Intermediate maturity non-U.S. fixed income
instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation
PIMCO Global Advantage® Strategy
Bond
U.S. and non-U.S. fixed income instruments
≤ 8 years
Max 15% of total
assets below B
No Limitation
PIMCO Global Bond Opportunities
(U.S. Dollar-Hedged)
U.S. and hedged non-U.S. intermediate maturity
fixed income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO Global Bond Opportunities
(Unhedged)
U.S. and non-U.S. intermediate maturity fixed
income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation
PIMCO Diversified Income
Investment grade corporate, high yield and
emerging market fixed income instruments
3 to 8 years
Max 10% below B
No Limitation
PIMCO Emerging Markets Local Currency
and Bond
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and fixed income instruments
+/-2 years of its
benchmark
Max 15% of total
assets below B
No Limitation(18)
PIMCO Emerging Markets Corporate
Bond
Diversified portfolio of fixed income
instruments economically tied to emerging
market countries
+/- 2 years of its
benchmark
Max 15% of total
assets below B
No Limitation
Absolute Return
PIMCO Dynamic Bond
Diversified portfolio of fixed income
instruments
(-3) to 8 years
Max 40% of total
assets below Baa
No Limitation(19)
PIMCO Strategic Bond
Diversified portfolio of fixed income
instruments
(-1) to 5 years
Max 20% of total
assets below Baa
No Limitation(20)
PIMCO Credit Opportunities Bond
Diversified portfolio of fixed income
instruments
0 to 6 years
Max 50% of total
assets below B-
No Limitation(5)
PIMCO TRENDS Managed Futures
Strategy
Financial and commodity-linked derivative
instruments selected by a quantitative strategy
and generally backed by a short to intermediate
duration portfolio which may consist of cash
equivalent securities and fixed income
instruments
N/A
No Limitation
No Limitation
PIMCO RAE Fundamental Advantage
PLUS
Long exposure to RAE US Large Model
Portfolio, short exposure to the S&P 500 Index,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO Climate Bond
Diversified portfolio of fixed income
instruments
2 to 8 years
Max 25% of total
assets below Baa
No Limitation(5)

  51


Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Domestic
Equity-Related
PIMCO RAE PLUS
Exposure to RAE US Large Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO StocksPLUS® Small
Russell 2000® Index derivatives backed by a
diversified portfolio of actively managed fixed
income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(21)
PIMCO StocksPLUS® Long Duration
S&P 500 Index derivatives backed by a
diversified portfolio of long-term fixed income
instruments
+/-2 years of
Bloomberg
Barclays
Long-Term
Government/Credit
Index(22)
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO StocksPLUS® Absolute Return
S&P 500 Index derivatives backed by a portfolio
of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS®
S&P 500 Index derivatives backed by a portfolio
of short-term fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO RAE PLUS Small
Exposure to RAE US Small Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE US
Exposure to RAE US Portfolio
N/A
N/A
0%
PIMCO RAE US Small
Exposure to RAE US Small Portfolio
N/A
N/A
0%
PIMCO RAFI ESG U.S. ETF
Component Securities of the RAFI ESG US Index
N/A
N/A
0%
PIMCO RAFI Dynamic Multi-Factor
U.S. Equity ETF
Component Securities of the RAFI Dynamic
multi-Factor US Index
N/A
N/A
0%
Equity-Related
PIMCO All Asset: Multi-RAE PLUS
Long exposure to a portfolio of stocks
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below Baa
(14)
No Limitation(21)
International
Equity-Related
PIMCO Dividend and Income
Exposure to RAE Income Global Portfolio in
Equity Sleeve; remainder of portfolio invests in
fixed income instruments of varying maturities
N/A
No Limitation
No Limitation
PIMCO RAE PLUS EMG
Exposure to RAE Emerging Markets Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(21)
PIMCO StocksPLUS® International
(Unhedged)
Non-U.S. equity derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(21)
PIMCO StocksPLUS® International
(U.S. Dollar-Hedged)
Non-U.S. equity derivatives (hedged to
U.S. dollars) backed by a portfolio of fixed
income instruments.
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(21)
PIMCO RAE PLUS International
Exposure to RAE International Large Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(11)
PIMCO RAE Worldwide Long/Short PLUS
Long exposure to RAE Low Volatility U.S. Model
Portfolio, RAE Low Volatility Intl Model Portfolio
and RAE Low Volatility EMG Model Portfolio,
short exposure to certain traditional
capitalization-weighted equity indexes,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(11)
PIMCO RAE Emerging Markets
Exposure to RAE Emerging Markets Portfolio
N/A
N/A
No Limitation
PIMCO RAE International
Exposure to RAE International Portfolio
N/A
N/A
No Limitation
PIMCO RAFI Dynamic Multi-Factor
Emerging Markets Equity ETF
Component securities of the RAFI Dynamic
Multi-Factor Emerging Markets Index
N/A
N/A
No Limitation
PIMCO RAFI Dynamic Multi-Factor
International Equity ETF
Component securities of the RAFI Dynamic
Multi-Factor Developed Ex-U.S. Index
N/A
N/A
No Limitation
U.S. Government
Securities
PIMCO Government Money Market
U.S. government securities
≤ 60 days
dollar-weighted
average maturity
Min 97% of total
assets Prime 1; ≤ 3%
of total assets Prime 2
0%

52  


Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Short Strategies
PIMCO StocksPLUS® Short
Short S&P 500 Index derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO All Asset: Multi-Short PLUS
Short exposure to equity markets
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below Baa
(14)
No Limitation(21)
Actively-Managed
Exchange-Traded
Funds
PIMCO Active Bond Exchange-Traded
Fixed income instruments of varying maturities
2 to 8 years
Max 30% of total
assets below Baa
0-15% of total
assets(4)
PIMCO Enhanced Low Duration Active
Exchange-Traded
Fixed income instruments of varying maturities
1 to 3 years
Max 15% below Baa
No Limitation(11)
PIMCO Enhanced Short Maturity Active
Exchange-Traded
Short to intermediate maturity fixed income
instruments
≤1 year
Baa to Aaa
0%
PIMCO Intermediate Municipal Bond
Active Exchange-Traded
Intermediate maturity municipal securities
(exempt from federal income tax)
(-2) to 4 years of
its benchmark
Baa to Aaa
0%
PIMCO Short Term Municipal Bond Active
Exchange-Traded
Short maturity municipal securities (exempt
from federal income tax)
≤ 3 years
Baa to Aaa
0%
PIMCO Enhanced Short Maturity Active
ESG Exchange-Traded
Short to intermediate maturity fixed income
instruments
≤1 year
Baa to Aaa
0-10% of total
assets
1
As rated by Moody's, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality.
2
Certain Underlying PIMCO Funds may invest beyond these limits in U.S. dollar-denominated instruments of non-U.S. issuers.
3
Such limitation shall not apply to the Fund's investments in mortgage- and asset-backed securities.
4
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 10% of its total assets.
5
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
6
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index.
7
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML Developed Markets High Yield Constrained (USD Hedged) Index.
8
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to within 10% (plus or minus) of the Fund's benchmark's foreign currency exposure.
9
The Fund may also invest up to an additional 5% of its total assets in mortgage-related high yield instruments rated below Baa.
10
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund. Information for the PIMCO Low Duration Credit Fund is effective as of May 3, 2021.
11
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 5% of its total assets.
12
Such limitation shall not apply to the Fund's investments in mortgage-related securities.
13
Within such limitation, the Fund may invest in mortgage-related securities rated below B.
14
Within such limitation, the Fund may invest in mortgage- and asset-backed securities rated below B.
15
With respect to the Fund's fixed income investments, the Fund will normally limit its foreign currency exposure (from non-U.S. dollar denominated securities or currencies) to 20% of its total assets.
16
The percentage limitation relates to Fixed Income Instruments of non-U.S. issuers denominated in any currency.
17
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or in Fixed Income Instruments denominated in the currencies of, emerging market countries, and in short-term investments.
18
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or Fixed Income Instruments denominated in the currencies of, emerging market countries and in Fixed Income Instruments, each of which may be represented by forwards or derivatives such as options, futures contracts or swap agreements.
19
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
20
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 25% of its total assets.
21
With respect to the Fund's fixed income investments, the Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
22
The Bloomberg Barclays Long-Term Government/Credit Index is an unmanaged index of U.S. Government or investment grade credit securities having a maturity of 10 years or more.

  53

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO All Asset Portfolio
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$10.91
$0.44
$0.38
$0.82
$(0.53)
$0.00
$0.00
$(0.53)
12/31/2019
10.05
0.36
0.83
1.19
(0.33)
0.00
0.00
(0.33)
12/31/2018
10.97
0.51
(1.07)
(0.56)
(0.36)
0.00
0.00
(0.36)
12/31/2017
10.11
0.58
0.80
1.38
(0.50)
0.00
(0.02)
(0.52)
12/31/2016
9.19
0.24
0.96
1.20
(0.26)
0.00
(0.02)
(0.28)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratios shown do not include expenses of the investment companies in which a Portfolio may invest. See the Fees and Expenses note in the Notes to Financial Statements for more information regarding the expenses and any applicable fee waivers associated with these investments.
(e)
Includes in-kind purchases and sales of underlying funds. Please see Investments in Securities, note in the Notes to Financial Statements for more information.

54  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets(d)
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.20
8.17%
$14,097
0.325%
0.425%
0.325%
0.425%
4.22%
(e)141%
10.91
11.92
11,788
0.275
0.425
0.275
0.425
3.36
31
10.05
(5.20)
10,616
0.305
0.425
0.305
0.425
4.78
37
10.97
13.77
12,827
0.325
0.425
0.325
0.425
5.43
40
10.11
13.08
5,726
0.275
0.425
0.275
0.425
2.43
67

April 30, 2021 | PROSPECTUS  55

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1875F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: M
Active Asset Allocation Portfolio – Real Return Oriented
PIMCO All Asset Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO All Asset Portfolio

Investment Objective
The Portfolio seeks maximum real return, consistent with preservation of real capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Class M shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Class M
Management Fees
0.425%
Distribution and/or Service (12b-1) Fees
0.45%
Acquired Fund Fees and Expenses(1)
0.80%
Total Annual Portfolio Operating Expenses(2)
1.675%
Fee Waiver and/or Expense Reimbursement(3)
(0.10%)
Total Annual Portfolio Operating Expenses After Fee Waiver and/or
Expense Reimbursement
1.575%
1
Acquired Fund Fees and Expenses include interest expense of the Underlying PIMCO Funds of 0.06%. Interest expense can result from certain transactions within the Underlying PIMCO Funds and is separate from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense of the Underlying PIMCO Funds, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 1.515% for Class M shares.
2
Total Annual Portfolio Operating Expenses do not match the Ratio of Expenses to Average Net Assets Excluding Waivers of the Portfolio, as set forth in the Financial Highlights table of the Portfolio’s prospectus, because the Ratio of Expenses to Average Net Assets Excluding Waivers reflects the operating expenses of the Portfolio and does not include Acquired Fund Fees and Expenses.
3
PIMCO has contractually agreed, through May 1, 2022, to reduce its advisory fee to the extent that the Underlying PIMCO Fund Expenses attributable to advisory and supervisory and administrative fees exceed 0.64% of the total assets invested in Underlying PIMCO Funds. PIMCO may recoup these waivers in future periods, not exceeding three years from the date of waiver, provided total expenses, including such recoupment, do not exceed the annual expense limit that was in place at the time the amount being recouped was originally waived and the current annual expense limit. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. The fee reduction is implemented based on a calculation of Underlying PIMCO Fund Expenses attributable to advisory and supervisory and administrative fees that is different from the calculation of Acquired Fund Fees and Expenses listed in the table above.
Example.The Example is intended to help you compare the cost of investing in Class M shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions.
The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Class M
$160
$518
$901
$1,973
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 141% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio is a “fund of funds,” which is a term used to describe mutual funds that pursue their investment objective by investing in other funds. The Portfolio seeks to achieve its investment objective by investing under normal circumstances substantially all of its assets in the least expensive class of shares of any actively managed or smart beta funds (including mutual funds or exchange-traded funds) of PIMCO Funds, PIMCO ETF Trust or PIMCO Equity Series, each an affiliated open-end investment company, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management (collectively, “Underlying PIMCO Funds”). As used in the investment objective, “real return” equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure, and “real capital” equals capital less the estimated cost of inflation measured by the change in an official inflation measure. In addition to investing in Underlying PIMCO Funds, at the discretion of PIMCO and without shareholder approval, the Portfolio may invest in additional Underlying PIMCO Funds created in the future.
The Portfolio invests its assets in shares of the Underlying PIMCO Funds and does not invest directly in stocks or bonds of other issuers. Research Affiliates, the Portfolio’s asset allocation sub-adviser, determines how the Portfolio allocates and reallocates its assets among the Underlying PIMCO Funds. In doing so, the asset allocation sub-adviser seeks concurrent exposure to a broad spectrum of asset classes.
Investments in Underlying PIMCO Funds.The Portfolio may invest in any or all of the Underlying PIMCO Funds, but will not normally invest in every Underlying PIMCO Fund at any particular time. The Portfolio’s investment in a particular Underlying PIMCO Fund normally will not exceed 50% of its total assets. The Portfolio will not invest in the Short Strategy Underlying PIMCO Funds, which seek to gain a negative exposure to an asset class such as equities. The Portfolio’s combined investments in the Equity-Related Underlying PIMCO Funds will not exceed 50% of its total assets. In addition, the Portfolio’s combined investments in Inflation-Related Underlying PIMCO Funds, which seek to gain exposure to an asset class such as U.S. Treasury Inflation-Protected Securities (“TIPS”), commodities, or real estate, normally will not exceed 75% of its total assets.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Asset Allocation Investment Process.The Portfolio’s assets are not allocated according to a predetermined blend of shares of the Underlying PIMCO Funds. Instead, when making allocation decisions among the Underlying PIMCO Funds, the Portfolio’s asset allocation sub-adviser considers various quantitative and qualitative data relating to the U.S. and foreign economies and securities markets. Such data includes projected growth trends in the U.S. and foreign economies, forecasts for interest rates and the relationship between short- and long-term interest rates (yield curve), current and projected trends in inflation, relative valuation levels in the equity and fixed income markets and various segments within those markets, the outlook and projected growth of various industrial sectors, information relating to business cycles, borrowing needs and the cost of capital, political trends, data relating to trade balances and labor information. The Portfolio’s asset allocation sub-adviser has the flexibility to reallocate the Portfolio’s assets among any or all of the asset class exposures represented by the Underlying PIMCO Funds based on its ongoing analyses of the equity, fixed income and commodity markets. While these analyses are performed daily, material shifts in asset class exposures typically take place over longer periods of time.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Principal Risks of the Portfolio
Allocation Risk:the risk that a Portfolio could lose money as a result of less than optimal or poor asset allocation decisions. The Portfolio could miss attractive investment opportunities by underweighting markets that subsequently experience significant returns and could lose value by overweighting markets that subsequently experience significant declines
Fund of Funds Risk:the risk that a Portfolio’s performance is closely related to the risks associated with the securities and other investments held by the Underlying PIMCO Funds and that the ability of a Portfolio to achieve its investment objective will depend upon the ability of the Underlying PIMCO Funds to achieve their investment objectives
Certain principal risks of investing in the Underlying PIMCO Funds, and consequently the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Certain Principal Risks of Underlying PIMCO Funds
Market Trading Risk:the risk that an active secondary trading market for shares of an Underlying PIMCO Fund that is an exchange-traded fund does not continue once developed, that such Underlying PIMCO Fund may not continue to meet a listing exchange’s trading or listing requirements, or that such Underlying PIMCO Fund’s shares trade at prices other than the Fund’s net asset value
Municipal Project-Specific Risk:the risk that an Underlying PIMCO Fund may be more sensitive to adverse economic, business or political
developments if it invests a substantial portion of its assets in the bonds of specific projects (such as those relating to education, health care, housing, transportation, and utilities), industrial development bonds, or in bonds from issuers in a single state
Municipal Bond Risk:the risk that an Underlying PIMCO Fund may be affected significantly by the economic, regulatory or political developments affecting the ability of issuers of debt securities whose interest is, in the opinion of bond counsel for the issuer at the time of issuance, exempt from federal income tax (“Municipal Bonds”) to pay interest or repay principal
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Distressed Company Risk:the risk that securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid

April 30, 2021 | PROSPECTUS  2

PIMCO All Asset Portfolio

investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. An Underlying PIMCO Fund’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Underlying PIMCO Fund’s ability to invest in derivatives, limit the Underlying PIMCO Fund’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Underlying PIMCO Fund’s performance
Futures Contract Risk:the risk that, while the value of a futures contract tends to correlate with the value of the underlying asset that it represents, differences between the futures market and the market for the underlying asset may result in an imperfect correlation. Futures contracts may involve risks different from, and possibly greater than, the risks associated with investing directly in the underlying assets. The purchase or sale of a futures contract may result in losses in excess of the amount invested in the futures contract
Model Risk:the risk that an Underlying PIMCO Fund’s investment models used in making investment allocation decisions, and the indexation methodologies used in constructing an underlying index for an Underlying PIMCO Fund that seeks to track the investment results of such underlying index, may not adequately take into account certain factors and may result in a decline in the value of an investment in the Underlying PIMCO Fund
Commodity Risk:the risk that investing in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies,
embargoes, tariffs and international economic, political and regulatory developments
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Real Estate Risk:the risk that the Portfolio’s investments in Real Estate Investment Trusts (“REITs”) or real estate-linked derivative instruments will subject the Portfolio to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. A Portfolio’s investments in REITs or real estate-linked derivative instruments subject it to management and tax risks. In addition, privately traded REITs subject a Portfolio to liquidity and valuation risk
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage,

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Smaller Company Risk:the risk that the value of securities issued by a smaller company may go up or down, sometimes rapidly and unpredictably as compared to more widely held securities, due to narrow markets and limited resources of smaller companies. A Portfolio’s investments in smaller companies subject it to greater levels of credit, market and issuer risk
Issuer Non-Diversification Risk:the risk of focusing investments in a small number of issuers, including being more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Portfolios that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified”
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO, or Research Affiliates, and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO or Research Affiliates to restrict or prohibit participation in certain investments.. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Tax Risk:the risk that the tax treatment of swap agreements and other derivative instruments, such as commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures, may be affected by future regulatory or legislative changes that could affect whether income from such investments is “qualifying income” under Subchapter M of the Internal Revenue Code, or otherwise affect the character, timing and/or amount of the Portfolio’s taxable income or gains and distributions
Subsidiary Risk:the risk that, by investing in certain Underlying PIMCO Funds that invest in a subsidiary (each a “Subsidiary”), the Portfolio is indirectly exposed to the risks associated with a Subsidiary’s investments. The Subsidiaries are not registered under the 1940 Act and may not be subject to all the investor protections of the 1940 Act. There is no guarantee that the investment objective of a Subsidiary will be achieved
Value Investing Risk:a value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
Exchange-Traded Fund Risk:the risk that an exchange-traded fund may not track the performance of the index it is designed to track, among other reasons, because of exchange rules, market prices of shares of an exchange-traded fund may fluctuate rapidly and materially, or shares of an exchange-traded fund may trade significantly above or below net asset value, any of which may cause losses to the Portfolio invested in the exchange-traded fund
Tracking Error Risk:the risk that the portfolio of an Underlying PIMCO Fund that seeks to track the investment results of an underlying index may not closely track the underlying index for a number of reasons. The Underlying PIMCO Fund incurs operating expenses, which are not applicable to the underlying index, and the costs of buying and selling securities, especially when rebalancing the Underlying PIMCO Fund’s portfolio to reflect changes in the composition of the underlying index. Performance of the Underlying PIMCO Fund and the underlying index may vary due to asset valuation differences and differences between the Underlying PIMCO Fund’s portfolio and the underlying index due to legal restrictions, cost or liquidity restraints. The risk that performance of the Underlying PIMCO Fund and the underlying index may vary may be heightened during periods of increased market volatility or other unusual market conditions. In addition, an Underlying PIMCO Fund’s use of a representative sampling approach may cause the Underlying PIMCO Fund to be less correlated to the return of the underlying index than if the Underlying PIMCO Fund held all of the securities in the underlying index
Indexing Risk:the risk that an Underlying PIMCO Fund that seeks to track the investment results of an underlying index is negatively affected by general declines in the asset classes represented by the underlying index
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by an Underlying PIMCO Fund rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Underlying PIMCO Fund or on certain instruments in which the Underlying PIMCO Fund invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in value of certain instruments held by the Underlying PIMCO Fund
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

April 30, 2021 | PROSPECTUS  4

PIMCO All Asset Portfolio

Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index and an index of similar funds. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Class M shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio measures its performance against a primary benchmark and a secondary benchmark. The Bloomberg Barclays U.S. TIPS: 1-10 Year Index, the primary benchmark, is an unmanaged index comprised of U.S. Treasury Inflation-Protected securities having a maturity of at least 1 year and less than 10 years. The CPI + 500 Basis Points benchmark, the secondary benchmark, is created by adding 5% to the annual percentage change in the Consumer Price Index (“CPI”). The CPI is an unmanaged index representing the rate of inflation of the U.S. consumer prices as determined by the U.S. Bureau of Labor Statistics.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Class M
Best Quarter
December 31, 2020
12.03%
Worst Quarter
March 31, 2020
-16.14%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Class M Return
7.74%
7.63%
4.34%
Bloomberg Barclays U.S. TIPS: 1-10 Year Index (reflects
no deductions for fees, expenses or taxes)
8.39%
4.13%
2.88%
Consumer Price Index + 500 Basis Points (reflects no
deductions for fees, expenses or taxes)
6.29%
6.94%
6.73%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. Research Affiliates serves as the asset allocation sub-adviser to the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Robert D. Arnott and Christopher J. Brightman. Mr. Arnott is the Chairman and Founder of Research Affiliates and he has managed the Portfolio since its inception in April 2003. Mr. Brightman is Chief Investment Officer of Research Affiliates and he has managed the Portfolio since November 2016.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

5  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments in the Underlying PIMCO Funds. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Underlying PIMCO Funds, and consequently the Portfolio, are identified in the Portfolio Summary and are described in this section. The Portfolio and the Underlying PIMCO Funds may be subject to additional risks other than those identified and described below because the types of investments made by an Underlying PIMCO Fund can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Underlying PIMCO Funds, their investments and the related risks. There is no guarantee that the Portfolio or the Underlying PIMCO Funds will be able to achieve their investment objectives. It is possible to lose money by investing in the Portfolio.
Allocation Risk
The Portfolio’s investment performance depends upon how its assets are allocated and reallocated between the Underlying PIMCO Funds according to the Portfolio’s asset allocation targets and ranges. A principal risk of investing in the Portfolio is that the asset allocation sub-adviser will make less than optimal or poor asset allocation decisions. The asset allocation sub-adviser attempts to identify investment allocations for the Underlying PIMCO Funds that will provide consistent, quality performance for the Portfolio, but there is no guarantee that such allocation techniques will produce the desired results. It is possible that the asset allocation sub-adviser will focus on an Underlying PIMCO Fund that performs poorly or underperforms other Underlying PIMCO Funds under various market conditions. You could lose money on your investment in the Portfolio as a result of these allocation decisions.
Fund of Funds Risk
Because the Portfolio invests substantially all of its assets in Underlying PIMCO Funds, the risks associated with investing in the Portfolio are closely related to the risks associated with the securities and other investments held by the Underlying PIMCO Funds. The ability of the Portfolio to achieve its investment objective will depend upon the ability of the Underlying PIMCO Funds to achieve their respective investment objectives. There can be no assurance that the investment objective of any Underlying PIMCO Fund will be achieved.
The Portfolio’s net asset value (“NAV”) will fluctuate in response to changes in the respective NAVs of the Underlying PIMCO Funds in which it invests. The extent to which the investment performance and risks associated with the Portfolio correlate to those of a particular Underlying PIMCO Fund will depend upon the extent to which the Portfolio’s assets are allocated from time to time for investment in the Underlying PIMCO Fund, which will vary. To the extent that the Portfolio invests a significant portion of its assets in an Underlying PIMCO Fund, it will be particularly sensitive to the risks associated with that Underlying PIMCO Fund.
Market Trading Risk
An Underlying PIMCO Fund that is an exchange-traded fund is subject to secondary market trading risks. Once operational, shares of the Underlying PIMCO Fund are listed for trading on an exchange, however, there can be no guarantee that an active trading market for such shares will develop or continue. Shares of the Underlying PIMCO Fund may be listed or traded on U.S. and foreign (non-U.S.) exchanges other than the Underlying PIMCO Fund’s primary U.S. listing exchange. There can be no guarantee that the Underlying PIMCO Fund’s shares will continue trading on any exchange or in any market or that the Underlying PIMCO Fund’s shares will continue to meet the listing or trading requirements of any exchange or market. The Underlying PIMCO Fund’s shares may experience higher trading volumes on one exchange as compared to another and investors are subject to the execution and settlement risks of the market where their broker directs trades.
Secondary market trading in the Underlying PIMCO Fund’s shares may be halted by an exchange because of market conditions. Pursuant to exchange or market rules, trading in the Underlying PIMCO Fund’s shares on an exchange or in any market may be subject to trading halts caused by extraordinary market volatility. If secondary market trading is halted or an exchange closes earlier than anticipated, you may be unable to purchase or sell Portfolio shares. There can be no guarantee that the Underlying PIMCO Fund’s exchange listing or ability to trade its shares will continue or remain unchanged. In the event the Underlying PIMCO Fund ceases to be listed on an exchange, the Underlying PIMCO Fund may cease operating as an “exchange-traded” fund and operate as a mutual fund, provided that shareholders are given advance notice.
Buying or selling the Underlying PIMCO Fund’s shares on an exchange may require the payment of brokerage commissions. In addition, an investor who buys or sells the Underlying PIMCO Fund’s shares may also incur the cost of the spread (the difference between the bid price and the ask price). The commission is frequently a fixed amount and may be a significant cost for investors seeking to buy or sell small amounts of shares. The spread varies over time for shares of the Underlying PIMCO Fund based on their trading volume and market liquidity, and is generally less if the Underlying PIMCO Fund has more trading volume and market liquidity and more if the Underlying PIMCO Fund has less trading volume and market liquidity. Due to the costs inherent in buying or selling the Underlying PIMCO Fund’s shares, frequent trading may detract significantly from investment returns. Investment in the Underlying PIMCO Fund’s shares may not be advisable for investors who expect to engage in frequent trading.

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Shares of the Underlying PIMCO Fund may trade on an exchange at prices at, above or below their most recent NAV. The market prices of an Underlying PIMCO Fund’s shares will fluctuate, sometimes rapidly and materially, in response to changes in the Underlying PIMCO Fund’s NAV, the value of the Underlying PIMCO Fund’s holdings and supply and demand for the Underlying PIMCO Fund’s shares. Although the creation/redemption feature of the Underlying PIMCO Funds generally makes it more likely that an Underlying PIMCO Fund’s shares will trade close to NAV, market volatility, lack of an active trading market for the Underlying PIMCO Fund’s shares, disruptions at market participants (such as authorized participants or market makers) and any disruptions in the ordinary functioning of the creation/redemption process may result in the Underlying PIMCO Fund’s shares trading significantly above (at a “premium”) or below (at a “discount”) NAV. An investor who buys or sells an Underlying PIMCO Fund’s shares may incur significant losses if the investor transacts in the Underlying PIMCO Fund’s shares in these and other circumstances. Neither PIMCO nor the Trust can predict whether an Underlying PIMCO Fund’s shares will trade above, below or at NAV. An Underlying PIMCO Fund’s investment results are based on the Underlying PIMCO Fund’s daily NAV. Investors transacting in an Underlying PIMCO Fund’s shares in the secondary market, where market prices may differ from NAV, may experience investment results that differ from results based on the Underlying PIMCO Fund’s daily NAV.
Municipal Project-Specific Risk
An Underlying PIMCO Fund may be more sensitive to adverse economic, business or political developments if it invests a substantial portion of its assets in the bonds of specific projects (such as those relating to education, health care, housing, transportation, and utilities), industrial development bonds, or in general obligation bonds, particularly if there is a large concentration from issuers in a single state.
Municipal Bond Risk
An Underlying PIMCO Fund that invests in Municipal Bonds may be affected significantly by the economic, regulatory or political developments affecting the ability of issuers of Municipal Bonds to pay interest or repay principal. In addition, the ability of an issuer to make payments or repay interest may be affected by litigation or bankruptcy. In the event of bankruptcy of such an issuer, an Underlying PIMCO Fund investing in the issuer’s securities could experience delays in collecting principal and interest, and the Underlying PIMCO Fund may not, in all circumstances, be able to collect all principal and interest to which it is entitled. To enforce its rights in the event of a default in the payment of interest or repayment of principal, or both, an Underlying PIMCO Fund may, in some instances, take possession of, and manage, the assets securing the issuer’s obligations on such securities, which may increase the Underlying PIMCO Fund’s operating expenses. Any income derived from the Underlying PIMCO Fund’s ownership or operation of such assets may not be tax-exempt. Municipal Bonds are subject to interest rate, credit and market risk.
Because many Municipal Bonds are issued to finance similar projects (such as those relating to education, health care, housing, transportation, and utilities), conditions in those sectors may affect the overall municipal securities market. In addition, changes in the financial condition of an individual municipal issuer can affect the overall municipal market. Municipal Bonds backed by current or anticipated revenues from a specific project or specific assets can be negatively affected by the discontinuance of the supporting taxation or the inability to collect revenues for the specific project or specific assets. Municipal Bonds are subject to the risk that the Internal Revenue Service (“IRS”) may determine that an issuer has not complied with applicable tax requirements and that interest from the Municipal Bond is taxable, which may result in a significant decline in the value of the security. Municipal Bonds may be less liquid than taxable bonds and there may be less publicly available information on the financial condition of Municipal Bond issuers than for issuers of other securities, and the investment performance of an Underlying PIMCO Fund investing in Municipal Bonds may therefore be more dependent on the analytical abilities of PIMCO than if the Underlying PIMCO Fund held other types of investments such as stocks or taxable bonds. The secondary market for Municipal Bonds also tends to be less well-developed or liquid than many other securities markets, a by-product of lower capital commitments to the asset class by the dealer community, which may adversely affect an Underlying PIMCO Fund’s ability to sell Municipal Bonds it holds at attractive prices or value Municipal Bonds.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in an Underlying PIMCO Fund’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Underlying PIMCO Fund is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and an Underlying PIMCO Fund may lose money as a result of movements in interest rates. An Underlying PIMCO Fund may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.

April 30, 2021 | PROSPECTUS  7

PIMCO Variable Insurance Trust

Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When an Underlying PIMCO Fund holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Underlying PIMCO Fund’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Underlying PIMCO Fund may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Underlying PIMCO Fund is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Underlying PIMCO Fund. This is especially the case if the Underlying PIMCO Fund consists of securities with widely varying durations. Therefore, if the Underlying PIMCO Fund has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Underlying PIMCO Fund uses leverage or derivatives in connection with the management of the Underlying PIMCO Fund.
Convexity is an additional measure used to understand a security’s or an Underlying PIMCO Fund‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Underlying PIMCO Fund holds such securities, the Underlying PIMCO Fund may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
An Underlying PIMCO Fund could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/ or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by an Underlying PIMCO Fund may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Underlying PIMCO Fund. This is especially the case if the Underlying PIMCO Fund consists of securities with widely varying credit ratings. Therefore, if the Underlying PIMCO Fund has an average credit rating that suggests a certain credit quality, the Underlying PIMCO Fund may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Underlying PIMCO Fund uses leverage or derivatives in connection with the management of the Underlying PIMCO Fund. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/ or interest.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

High Yield Risk
Underlying PIMCO Funds that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Distressed Company Risk
An Underlying PIMCO Fund that invests in securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments. Issuers of distressed company securities may also be involved in restructurings or bankruptcy proceedings that may not be successful. An economic downturn or period of rising interest rates could adversely affect the market for these securities and reduce the Underlying PIMCO Fund’s ability to sell these securities (liquidity risk). If the issuer of a debt security is in default with respect to interest or principal payments, the Underlying PIMCO Fund may lose its entire investment.
Market Risk
The market price of securities owned by an Underlying PIMCO Fund may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors which affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by an Underlying PIMCO Fund. Even when markets perform well, there is no assurance that the investments held by an Underlying PIMCO Fund will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Underlying PIMCO Funds to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Underlying PIMCO Funds’ investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi- governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the

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ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent an Underlying PIMCO Fund from executing advantageous investment decisions in a timely manner. Underlying PIMCO Funds that have focused their investments in a region enduring geopolitical market disruption will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to an Underlying PIMCO Fund’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Underlying PIMCO Fund to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause an Underlying PIMCO Fund to lose enough value, the Underlying PIMCO Fund could also face increased shareholder redemptions, which could force the Underlying PIMCO Fund to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Underlying PIMCO Fund.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, an Underlying PIMCO Fund being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAVs, delays in NAV calculation and/or the inability to calculate NAVs over extended periods.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Underlying PIMCO Funds reasonably expect cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. An Underlying PIMCO Fund’s investments in illiquid investments may reduce the returns of the Underlying PIMCO Fund because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Underlying PIMCO Fund to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Underlying PIMCO Fund from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, an Underlying PIMCO Fund, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that an Underlying PIMCO Fund principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Underlying PIMCO Fund will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for an Underlying PIMCO Fund to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require an Underlying PIMCO Fund to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Underlying PIMCO Fund, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.

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Prospectus

Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Underlying PIMCO Funds may use are referenced under “Characteristics and Risks of Securities and Investment Techniques-Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. Underlying PIMCO Funds may also use derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. Underlying PIMCO Funds may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject an Underlying PIMCO Fund to the potential for unlimited loss. The use of derivatives may cause the Underlying PIMCO Fund’s investment returns to be impacted by the performance of securities the Underlying PIMCO Fund does not own and result in the Underlying PIMCO Fund’s total investment exposure exceeding the value of its portfolio.
An Underlying PIMCO Fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of the derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Underlying PIMCO Fund may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Underlying PIMCO Fund are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Underlying PIMCO Fund, or the derivatives or other strategies used by the Underlying PIMCO Fund, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Underlying PIMCO Fund invests. By investing in a derivative instrument, the Underlying PIMCO Fund could lose more than the initial amount invested, and derivatives may increase the volatility of the Underlying PIMCO Fund, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that an Underlying PIMCO Fund will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, an Underlying PIMCO Fund’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders.
Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Underlying PIMCO Fund’s clearing broker, or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which an Underlying PIMCO Fund may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If an Underlying PIMCO Fund incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Underlying PIMCO Fund might have been in a better position if the Underlying PIMCO Fund had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Underlying PIMCO Fund and its counterparty. Therefore, it may not be possible for an Underlying PIMCO Fund to modify, terminate, or offset the Underlying PIMCO Fund’s obligations or the Underlying PIMCO Fund’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Underlying PIMCO Fund. In such case, the Underlying PIMCO Fund may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, an Underlying PIMCO Fund may wish to retain the Underlying PIMCO Fund’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, an Underlying PIMCO Fund will be subject to increased liquidity and investment risk.

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When a derivative is used as a hedge against a position that an Underlying PIMCO Fund holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that an Underlying PIMCO Fund’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of an Underlying PIMCO Fund’s derivative transactions, impede the employment of the Underlying PIMCO Fund’s derivatives strategies, or adversely affect the Underlying PIMCO Fund’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Underlying PIMCO Funds' asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Underlying PIMCO Funds to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Underlying PIMCO Funds to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Underlying PIMCO Funds' ability to employ certain strategies that use these instruments and/or adversely affect the Underlying PIMCO Funds' performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Underlying PIMCO Funds' investments and cost of doing business, which could adversely affect investors.
Futures Contract Risk
A futures contract is an exchange-traded contract to buy or sell an underlying asset, such as a security, currency or commodity, for a set price on a future date. The risks associated with the Underlying PIMCO Fund’s use of derivative instruments, including futures contracts, are discussed in more detail under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and under “Investment Objectives and Policies” in the SAI. The purchase or sale of a futures contract may result in losses in excess of the amount invested in the futures contract. There can be no guarantee that there will be a correlation between price movements in the futures contract and the underlying asset. In addition, there are significant differences between the futures market and the markets for underlying assets, which could result in an imperfect correlation between the markets. The degree of imperfect correlation depends on circumstances such as variations in speculative market demand for futures and futures options on underlying assets, including technical influences in futures trading and futures options, and differences between the futures contract and underlying asset due to factors such as interest rate levels, maturities, and creditworthiness of issuers.
Futures contracts are traded on exchanges, so that, in most cases, a party can close out its position on the exchange for cash, without delivering the underlying asset. Because the futures utilized by certain Underlying PIMCO Funds are exchange-traded, the primary credit risk on futures contracts resides with the Underlying PIMCO Fund’s clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Underlying PIMCO Fund’s ability to invest in derivatives, limit an Underlying PIMCO Fund’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio's performance. Futures exchanges may limit the amount of fluctuation permitted in certain futures contract prices during a single trading day. There can be no assurance that a liquid market will exist at a time when an Underlying PIMCO Fund seeks to close out a futures or a futures option position, and that the Portfolio or Underlying PIMCO Fund would remain obligated to meet margin requirements until the position is closed.
In addition, certain futures contracts may be relatively new instruments without a significant trading history. As a result, there can be no assurance that an active secondary market will develop or continue to exist.
Model Risk
In making investment allocation decisions for a Portfolio or certain Underlying PIMCO Funds, as applicable, PIMCO or the Sub-Adviser, as applicable, may utilize quantitative models that may be proprietary or developed by third-parties. These models are used by PIMCO or the Sub-Adviser, as applicable, to determine (or assist in determining) the Portfolio’s or Underlying PIMCO Fund’s target asset allocation and to identify potentially attractive relative value and risk hedging strategies. The investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in a Portfolio or Underlying PIMCO Fund. There can be no assurance that the models used by PIMCO or the Sub-Adviser, as applicable, will remain viable, due to various factors, which may include the quality of the data input into the models and the assumptions underlying such models, which to varying degrees involve the exercise of judgment, as well as the possibility of errors in constructing or using the model. In addition, in constructing the underlying index of, or model portfolio for, an Underlying PIMCO Fund that seeks to track the investment results of such underlying index or model portfolio, the index provider or sub-adviser, as applicable, may utilize quantitative models or

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Prospectus

methodologies that may be proprietary or developed by third-parties. These models and methodologies are used to help determine the composition of the underlying index or model portfolio and may not adequately take into account certain factors, resulting in a decline in the value of the underlying index or model portfolio and, therefore, the Underlying PIMCO Fund.
Models rely on accurate market data inputs. If inaccurate market data is entered into a model, the resulting information will be incorrect. In addition, the models used may be predictive in nature and such models may result in an incorrect assessment of future events. The models evaluate securities or securities markets based on certain assumptions concerning the interplay of market factors. The markets or the prices of individual securities may be affected by factors not foreseen in developing the models. In addition, when relying on a quantitative model and/or data supplied by third parties, PIMCO or the Sub-Adviser may have less insight into the construction, coding or testing of the third-party model or data, and PIMCO and the Sub-Adviser will be exposed to systems, cyber security and other risks associated with the third party that provides the model or data.
The use of models can be complex and involves financial, economic, econometric and statistical theories, research and modeling; and the results of those processes must then be translated into computer code. Although PIMCO and the Sub-Adviser seek to hire individuals and/or third parties, as applicable, skilled in each of these functions and to provide appropriate levels of oversight, the complexity of the individual tasks, the difficulty of integrating such tasks, and the limited ability to perform “real world” testing of a model’s end product raises the chances that a finished model may contain an error; one or more of such errors could adversely affect a Portfolio’s or an Underlying PIMCO Fund’s performance.
Commodity Risk
An Underlying PIMCO Fund’s investments in commodity-linked derivative instruments may subject the Underlying PIMCO Fund to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments. Certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund® , may each concentrate its assets in a particular sector of the commodities market (such as oil, metal or agricultural products). As a result, to the extent the Portfolio invests in the PIMCO CommoditiesPLUS® Strategy Fund or PIMCO CommodityRealReturn Strategy Fund® , each an Underlying PIMCO Fund, the Portfolio may be more susceptible to risks associated with those sectors. The prices for commodities in those sectors may fluctuate widely due to factors such as changes in value, supply and demand and governmental regulatory policies.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if an Underlying PIMCO Fund holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing an Underlying PIMCO Fund to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an Underlying PIMCO Fund to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of an Underlying PIMCO Funds because the Underlying PIMCO Fund may have to reinvest that money at the lower prevailing interest rates. An Underlying PIMCO Fund’s investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
Certain Underlying PIMCO Funds may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than portfolios that invest exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers.
Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Underlying PIMCO Fund’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Underlying PIMCO Fund could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that an Underlying PIMCO Fund invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Underlying PIMCO Fund will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Real Estate Risk
Underlying PIMCO Funds that invest in real estate investment trusts (“REITs”) or real estate-linked derivative instruments are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. An investment in a REIT or a real estate-linked derivative instrument that is linked to the value of a REIT is subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (the “Code”). In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. Finally, private REITs are not traded on a national securities exchange. As such, these products are generally illiquid. This reduces the ability of an Underlying PIMCO Fund to redeem its investment early. Private REITs are also generally harder to value and may bear higher fees than public REITs
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent an Underlying PIMCO Fund invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, technical, political and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent an Underlying PIMCO Fund invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Underlying PIMCO Fund may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. An Underlying PIMCO Fund that focuses its investments in multiple asset classes of emerging marketsecurities may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. An Underlying PIMCO Fund may also be subject to Emerging Markets Risk if they invest in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Underlying PIMCO Funds could lose money the economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers of such emerging markets may be more affected by the performance of such industries or sectors..

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Prospectus

Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If an Underlying PIMCO Fund invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, an Underlying PIMCO Fund’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that an Underlying PIMCO Fund invests in foreign (non-U.S.)currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Issuer Non-Diversification Risk
Focusing investments in a small number of issuers increases risk. Underlying PIMCO Funds that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than Underlying PIMCO Funds that are “diversified.” Underlying PIMCO Funds that invest in a relatively small number of issuers are more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Some of those issuers also may present substantial credit or other risks.
To the extent that the Portfolio invests a significant portion of its assets in an Underlying PIMCO Fund, the Portfolio will be particularly sensitive to the risks associated with that Underlying PIMCO Fund. For a discussion of risks associated with Underlying PIMCO Funds, please see “Fund of Funds Risk” above.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate its leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. Underlying PIMCO Funds also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause an Underlying PIMCO Fund to liquidate portfolio positions to satisfy its obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause an Underlying PIMCO Fund to be more volatile than if the Underlying PIMCO Fund had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Underlying PIMCO Fund’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Underlying PIMCO Fund does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where an Underlying PIMCO Fund, for any reason, is unable to close out the transaction. In addition, to the extent an Underlying PIMCO Fund borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed an Underlying PIMCO Fund’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, an Underlying PIMCO Fund may be forced to sell portfolio securities when it is not otherwise advantageous to do so.

April 30, 2021 | PROSPECTUS  15

PIMCO Variable Insurance Trust

Smaller Company Risk
The general risks associated with fixed income securities and equity securities are particularly pronounced for securities issued by companies with smaller market capitalizations. These companies may have limited product lines, markets or financial resources or they may depend on a few key employees. As a result, they may be subject to greater levels of credit, market and issuer risk. Securities of smaller companies may trade less frequently and in lesser volumes than more widely held securities and their values may fluctuate more sharply than other securities. Companies with medium-sized market capitalizations may have risks similar to those of smaller companies.
Management Risk
Certain Underlying PIMCO Funds are subject to management risk because they are actively managed investment portfolios. PIMCO or the Sub-Adviser, as applicable, and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Underlying PIMCO Funds, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which an Underlying PIMCO Fund seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Underlying PIMCO Fund. To the extent the Underlying PIMCO Fund employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Underlying PIMCO Fund. Certain Underlying PIMCO Funds are also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Underlying PIMCO Fund or hinder Underlying PIMCO Fund operations. For example, trading delays or errors (both human and systematic) could prevent an Underlying PIMCO Fund from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Underlying PIMCO Funds and may also adversely affect the ability of the Underlying PIMCO Funds to achieve their investment objectives. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on an Underlying PIMCO Fund’s ability to realize its investment objective.
Because a number of Underlying PIMCO Funds obtain exposure to certain proprietary model stock portfolios by investing in equity total return swaps based on such model portfolios, in other securities and instruments to replicate the performance of such model portfolios, or directly in the equity securities held in such model portfolios, such Underlying PIMCO Funds will be subject to the risks associated with the management of these proprietary model stock portfolios by the sub-adviser to such Underlying PIMCO Funds. Similarly, there can be no assurance that quantitative models or methods utilized by PIMCO or the Sub-Adviser or related data sources will always be available, and the loss of access to any such model(s) or data sources could have an adverse impact on the Underlying PIMCO Fund's ability to realize its investment objective.
Short Exposure Risk
An Underlying PIMCO Fund’s short sales, if any, are subject to special risks. A short sale involves the sale by the Underlying PIMCO Fund of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. An Underlying PIMCO Fund may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Underlying PIMCO Fund will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, an Underlying PIMCO Fund could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase an Underlying PIMCO Fund’s exposure to long security positions and make any change in the Underlying PIMCO Fund’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy an Underlying PIMCO Fund employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, an Underlying PIMCO Fund may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Underlying PIMCO Fund.

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Risk
The PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund in which the Portfolio may invest, gain exposure to the commodities markets through investments in commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures. The PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund may also gain exposure indirectly to commodity markets by investing in their respective subsidiaries (the “Subsidiaries”), which invest primarily in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and/or other Fixed Income Instruments. In order for each Underlying PIMCO Fund to qualify as a regulated investment company under Subchapter M of the Code, the Underlying PIMCO Fund must derive at least 90 percent of its gross income each taxable year from certain qualifying sources of income.
As more fully described below under “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” the IRS issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. The IRS has issued private letter rulings in which the IRS specifically concluded that income derived from the Underlying PIMCO Fund’s investment in its Subsidiary will also constitute qualifying income to each Underlying PIMCO Fund. Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if an Underlying PIMCO Fund‘s income from an investment in the subsidiary is distributed annually or is derived with respect to the Underlying PIMCO Fund’s business of investing in securities. An IRS revenue procedure states that the IRS will issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the Investment Company Act of 1940, as amended (the “1940 Act”).
Each Underlying PIMCO Fund will seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in its respective Subsidiary. If the IRS were to determine that income derived from certain commodity-linked notes or from investments in the Subsidiary does not constitute qualifying income, the Portfolio and certain Underlying PIMCO Funds, including the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund, might be adversely affected and would be required to reduce their exposure to such investments which might result in difficulty in implementing their investment strategies and increased costs and taxes. The use of commodity index-linked notes and investments in the Subsidiaries involve specific risks. See “Characteristics and Risks of Securities and Investment Techniques-Derivatives-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” below for further information regarding commodity index-linked notes, including the risks associated with these instruments. In addition, see “Characteristics and Risks of Securities and Investment Techniques-Investments in a Wholly-Owned Subsidiary” below for further information regarding the Subsidiaries, including the risks associated with investing in the Subsidiaries.
To the extent the Portfolio invests in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund®, or PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, the use of the above noted investments by the Underlying PIMCO Fund could subject the shareholders of the Portfolio to risks similar to those borne by shareholders of the PIMCO CommodityRealReturn® Strategy and PIMCO Global Managed Asset Allocation Portfolios. See “Tax Consequences.”
Subsidiary Risk
By investing in their respective Subsidiaries, the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund, Underlying PIMCO Funds, are indirectly exposed to the risks associated with the respective Subsidiary’s investments. The investments held by the Subsidiaries are generally similar to those that are permitted to be held by these Underlying PIMCO Funds and are subject to the same risks that apply to similar investments if held directly by the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund or PIMCO TRENDS Managed Futures Strategy Fund. These risks are described elsewhere in this prospectus. There can be no assurance that the investment objectives of the Underlying PIMCO Funds or the Subsidiaries will be achieved.
The Subsidiaries are not registered under the 1940 Act, and, unless otherwise noted in this prospectus, are not subject to all the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund and/or the Subsidiaries to operate as described in this prospectus and the SAI and could adversely affect the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund and, to the extent the Portfolio invests in the PIMCO CommodityRealReturn Strategy Fund®, PIMCO CommoditiesPLUS® Strategy Fund and PIMCO TRENDS Managed Futures Strategy Fund, the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of an Underlying PIMCO Fund and/or a Subsidiary and result in the Underlying PIMCO Fund underperforming its benchmark index(es).

April 30, 2021 | PROSPECTUS  17

PIMCO Variable Insurance Trust

Value Investing Risk
Value investing attempts to identify companies that are believed to be undervalued. Value stocks typically have prices that are low relative to factors such as the company’s earnings, cash flow or dividends. A value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur. A value investing style may perform better or worse than equity portfolios that focus on growth stocks or that have a broader investment style.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.
Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
Exchange-Traded Fund (“ETF”) Risk
Investments in ETFs entail certain risks. Investments in ETFs designed to track an index involve the risk that the ETF’s performance may not track the performance of the index the ETF is designed to track. This deviation may occur due to cash inflows and outflows from and to investors buying and redeeming shares or due to occasional differences between the composition of the index and the securities held by the ETF. In addition, investments in ETFs involve the risk that the market prices of ETF shares will fluctuate, sometimes rapidly and materially, in response to changes in the ETF’s NAV, the value of ETF holdings and supply and demand for ETF shares. Although ETFs will generally trade close to NAV, market volatility, lack of an active trading market for ETF shares, disruptions at market participants (such as Authorized Participants or market makers) and any disruptions in the ordinary functioning of the creation/redemption process may result in ETF shares trading significantly above (at a “premium”) or below (at a “discount”) NAV. Significant losses may result when transacting in ETF shares in these and other circumstances.
Tracking Error Risk
An Underlying PIMCO Fund that seeks to track the investment results of an index may not invest in every component security of its underlying index. Imperfect correlation between an Underlying PIMCO Fund’s portfolio and its underlying index, asset valuation, timing variances, changes to the underlying index and regulatory requirements may cause the Underlying PIMCO Fund’s performance to diverge from the performance of its underlying index. Tracking error may also result because an Underlying PIMCO Fund incurs fees and expenses while its underlying index does not incur such fees and expenses. Such expenses include the costs of buying and selling securities, such as when an Underlying PIMCO Fund rebalances its portfolio to reflect changes in the composition of the underlying index. These expenses may be higher for an Underlying PIMCO Fund investing in foreign (non-U.S.) securities. The performance of an Underlying PIMCO Fund and the underlying index may vary due to differences between the Underlying PIMCO Fund’s portfolio and the underlying index due to legal restrictions, cost or liquidity restraints. The risk that performance of an Underlying PIMCO Fund and the underlying index may vary may be heightened during periods of market volatility or other unusual market conditions. Because an underlying index is not subject to the tax diversification requirements to which an Underlying PIMCO Fund must adhere, the Underlying PIMCO Fund may be required to deviate its investments from the securities and relative weightings of its underlying index. For tax efficiency purposes, an Underlying PIMCO Fund may sell certain securities to realize losses, which will result in a deviation from its underlying index. An Underlying PIMCO Fund may not be fully invested at times either as a result of cash flows into the Fund or reserves of cash held by the Fund to meet redemptions and to

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

pay expenses. In addition, if an Underlying PIMCO Fund uses a representative sampling approach, this approach may cause the Underlying PIMCO Fund to be less correlated with the return of the underlying index than if the Underlying PIMCO Fund held all of the securities in the underlying index with the same relative weightings as the underlying index.
Indexing Risk
Certain Underlying PIMCO Funds use an indexing approach and may be affected by a general decline in market segments or asset classes relating to their underlying indexes. Those Underlying PIMCO Funds invest in securities and instruments included in, or representative of, their underlying indexes regardless of the investment merits of the underlying indexes. Additionally, errors in the construction or calculation of an Underlying PIMCO Fund’s underlying index may occur from time to time, and the index provider may not identify or correct such errors for some period of time. Any such underlying index construction or calculation error may adversely impact the Underlying PIMCO Fund.
LIBOR Transition Risk
Certain instruments in which an Underlying PIMCO Fund may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on an Underlying PIMCO Fund or on certain instruments in which an Underlying PIMCO Fund invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of an Underlying PIMCO Fund's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by an Underlying PIMCO Fund or a reduction in the effectiveness of related Underlying PIMCO Fund transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of an Underlying PIMCO Fund that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to an Underlying PIMCO Fund.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

April 30, 2021 | PROSPECTUS  19

PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
PIMCO has engaged Research Affiliates, a California limited liability company (“Research Affiliates”), to serve as the asset allocation sub-adviser to the PIMCO All Asset Portfolio. Research Affiliates was organized in 2002 and is located at 620 Newport Center Drive, Suite 900, Newport Beach, CA 92660. As asset allocation sub-adviser for this Portfolio, Research Affiliates is responsible for recommending how the assets of the Portfolio are allocated and reallocated from time to time among the Underlying PIMCO Funds.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.425% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.175% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract and asset allocation sub-advisory agreement is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Class M shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Class M shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) . PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Class M shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.

20  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Fund of Funds Fees
The Portfolio is permitted to invest in Underlying PIMCO Funds, which, for the Portfolio, is defined to include the least expensive class of shares of any actively managed or smart beta funds (including mutual funds or exchange-traded funds) of PIMCO Funds, PIMCO ETF Trust or PIMCO Equity Series, each an affiliated open-end investment company, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. Shares of the PIMCO All Asset: Multi-Real Fund, PIMCO All Asset: Multi-RAE PLUS Fund and PIMCO All Asset: Multi-Short PLUS Fund (the “PAPS All Asset Funds”) may be purchased only by the Portfolio, as well as by the PIMCO All Asset Fund and PIMCO All Asset All Authority Fund, each a series of PIMCO Funds, an affiliated investment company. 
The Portfolio pays advisory fees directly to PIMCO at an annual rate of 0.175% based on the average daily net assets attributable in the aggregate to the Portfolio’s Class M shares. The Portfolio pays supervisory and administrative fees directly to PIMCO at an annual rate of 0.25% based on the average daily net assets attributable in the aggregate to the Portfolio’s Class M shares. The Portfolio also indirectly pays its proportionate share of the advisory, supervisory and administrative and management fees charged by PIMCO to the Underlying PIMCO Funds and, to the extent not included among the Underlying PIMCO Funds, funds of PIMCO ETF Trust in which the Portfolio invests (collectively, “Underlying PIMCO Fund Fees”).
PIMCO has contractually agreed, through May 1, 2022, to waive the Portfolio’s advisory fee to the extent that the Underlying PIMCO Fund Fees exceed 0.64% of the total assets invested in Underlying PIMCO Funds. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the advisory fee waived as set forth above (the “Asset Allocation Reimbursement Amount”) during the previous thirty-six months from the time of waiver, provided that such amount paid to PIMCO will not: 1) together with any Underlying PIMCO Fund Fees exceed, for such month, the applicable expense limit; 2) exceed the total Asset Allocation Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
The Acquired Fund Fees and Expenses shown in the Annual Portfolio Operating Expenses table for the Portfolio may be higher than the Underlying PIMCO Fund Fees used for purposes of the Expense Reduction shown in that table due to differences in the methods of calculation. The Acquired Fund Fees and Expenses, as required to be shown in the Annual Portfolio Operating Expenses table, are calculated using the total operating expenses for each Underlying PIMCO Fund over the Portfolio’s average net assets. The Underlying PIMCO Fund Fees that are used for purposes of implementing the expense reduction described above are calculated using the advisory and supervisory and administrative fees for each Underlying PIMCO Fund over the total assets invested in Underlying PIMCO Funds. Thus, the Acquired Fund Fees and Expenses listed in the Annual Portfolio Operating Expenses table will typically be higher than the Underlying PIMCO Fund Fees used to calculate the Expense Reduction when the Portfolio employs leverage as an investment strategy.
The expenses associated with investing in a fund of funds are generally higher than those for mutual funds that do not invest in other funds. The cost of investing in the Portfolio will generally be higher than the cost of investing in a portfolio that invests directly in individual stocks and bonds. By investing in the Portfolio, an investor may indirectly bear a portion of the fees and expenses charged by Underlying PIMCO Funds, to the extent such fees and expenses are not waived or reimbursed pursuant to applicable waiver and reimbursement agreements, in addition to the Portfolio’s direct fees and expenses. In addition, the use of a fund of funds structure could affect the timing, amount and character of distributions to shareholders and may therefore increase the amount of taxes payable by shareholders. The Portfolio invests in the least expensive class of shares of the Underlying PIMCO Funds, which are not subject to any sales charges or distribution (12b-1) fees.
The following table summarizes the annual expenses borne by Institutional Class or Class M shareholders of the Underlying PIMCO Funds (or, in the case of the PAPS All Asset Funds and those operating as exchange-traded funds, the Underlying PIMCO Fund shareholders). Because the Portfolio invests in the least expensive class of shares of the Underlying PIMCO Funds, shareholders of the Portfolio would indirectly bear a proportionate share of these expenses, depending upon how the Portfolio’s assets are allocated from time to time among the Underlying PIMCO Funds.
For a complete description of an Underlying PIMCO Fund, please see the Underlying PIMCO Fund’s Institutional Class or Class M prospectus or offering memorandum, as applicable. For a summary description of the Underlying PIMCO Funds, please see the “Descriptions of the Underlying PIMCO Funds” section in this prospectus.
Annual Underlying PIMCO Fund Expenses
(Based on the average daily net assets attributable to an Underlying PIMCO Fund’s Institutional Class shares (or Class M shares in the case of the PIMCO Government Money Market Fund , or the Fund in the case of the PAPS All Asset Funds and exchange-traded funds of the PIMCO ETF Trust or PIMCO Equity Series)).)).
Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO Active Bond Exchange-Traded Fund
0.55%
0.02%
0.57%
PIMCO All Asset: Multi-RAE PLUS Fund
0.89%
0.00%
0.89%
PIMCO All Asset: Multi-Real Fund
0.74%
0.12%
0.86%(3)

April 30, 2021 | PROSPECTUS  21

PIMCO Variable Insurance Trust

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO All Asset: Multi-Short PLUS Fund
0.74%
0.02%
0.76%(3)
PIMCO California Intermediate Municipal Bond Fund
0.445%
0.00%
0.445%
PIMCO California Municipal Bond Fund
0.44%
0.02%
0.46%
PIMCO California Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Climate Bond Fund
0.50%
0.00%
0.50%
PIMCO CommoditiesPLUS® Strategy Fund
0.74%
0.27%
1.01%(4)
PIMCO CommodityRealReturn Strategy Fund®
0.74%
0.76%
1.50%(5)
PIMCO Credit Opportunities Bond Fund
0.90%
0.02%
0.92%
PIMCO Diversified Income Fund
0.75%
0.04%
0.79%
PIMCO Dividend and Income Fund
0.75%
0.05%
0.80%(6)
PIMCO Dynamic Bond Fund
0.80%
0.05%
0.85%
PIMCO Emerging Markets Bond Fund
0.83%
0.05%
0.88%
PIMCO Emerging Markets Corporate Bond Fund
0.90%
0.12%
1.02%
PIMCO Emerging Markets Currency and Short-Term Investments Fund
0.85%
0.03%
0.88%
PIMCO Emerging Markets Local Currency and Bond Fund
0.90%
0.80%
1.70%
PIMCO Enhanced Low Duration Active Exchange-Traded Fund
0.46%
0.10%
0.56%
PIMCO Enhanced Short Maturity Active ESG Exchange-Traded Fund
0.36%
0.03%
0.39%(7)
PIMCO Enhanced Short Maturity Active Exchange-Traded Fund
0.35%
0.02%
0.37%
PIMCO ESG Income Fund
0.50%
0.07%
0.57%(8)
PIMCO Extended Duration Fund
0.50%
1.21%
1.71%
PIMCO Global Advantage® Strategy Bond Fund
0.65%
0.21%
0.86%
PIMCO Global Bond Opportunities Fund (U.S. Dollar-Hedged)
0.55%
0.04%
0.59%
PIMCO Global Bond Opportunities Fund (Unhedged)
0.55%
0.12%
0.67%
PIMCO GNMA and Government Securities Fund
0.50%
0.33%
0.83%
PIMCO Government Money Market Fund
0.18%
0.00%
0.18%(9)
PIMCO High Yield Fund
0.55%
0.02%
0.57%
PIMCO High Yield Municipal Bond Fund
0.55%
0.08%
0.63%
PIMCO High Yield Spectrum Fund
0.60%
0.02%
0.62%
PIMCO Income Fund
0.50%
0.59%
1.09%
PIMCO Intermediate Municipal Bond Active Exchange-Traded Fund
0.35%
0.00%
0.35%
PIMCO International Bond Fund (U.S. Dollar-Hedged)
0.50%
0.10%
0.60%
PIMCO International Bond Fund (Unhedged)
0.50%
0.13%
0.63%
PIMCO Investment Grade Credit Bond Fund
0.50%
0.35%
0.85%
PIMCO Long Duration Total Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term Credit Bond Fund
0.55%
0.29%
0.84%
PIMCO Long-Term Real Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term U.S. Government Fund
0.475%
1.38%
1.855%
PIMCO Low Duration Credit Fund(10)
0.70%
0.05%
0.75%
PIMCO Low Duration ESG Fund
0.50%
0.08%
0.58%
PIMCO Low Duration Fund
0.46%
0.41%
0.87%
PIMCO Low Duration Fund II
0.50%
0.03%
0.53%
PIMCO Low Duration Income Fund
0.50%
0.05%
0.55%
PIMCO Moderate Duration Fund
0.46%
0.15%
0.61%
PIMCO Mortgage Opportunities and Bond Fund
0.60%
1.22%
1.82%
PIMCO Mortgage-Backed Securities Fund
0.50%
0.25%
0.75%
PIMCO Municipal Bond Fund
0.44%
0.07%
0.51%
PIMCO National Intermediate Municipal Bond Fund
0.45%
0.00%
0.45%
PIMCO New York Municipal Bond Fund
0.445%
0.05%
0.495%
PIMCO Preferred and Capital Securities Fund
0.79%
0.09%
0.88%(11)
PIMCO RAE Emerging Markets Fund
0.75%
0.02%
0.77%(6)
PIMCO RAE Fundamental Advantage PLUS Fund
0.89%
0.07%
0.96%
PIMCO RAE International Fund
0.50%
0.02%
0.52%(6)

22  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO RAE PLUS EMG Fund
1.10%
0.21%
1.31%
PIMCO RAE PLUS Fund
0.79%
0.08%
0.87%
PIMCO RAE PLUS International Fund
0.82%
0.05%
0.87%
PIMCO RAE PLUS Small Fund
0.84%
0.09%
0.93%
PIMCO RAE US Fund
0.40%
0.02%
0.42%(6)
PIMCO RAE US Small Fund
0.50%
0.04%
0.54%
PIMCO RAE Worldwide Long/Short PLUS Fund
1.19%
0.09%
1.28%
PIMCO RAFI Dynamic Multi-Factor Emerging Markets Equity ETF
0.49%
0.01%
0.50%(12)
PIMCO RAFI Dynamic Multi-Factor International Equity ETF
0.39%
0.02%
0.41%(12)
PIMCO RAFI Dynamic Multi-Factor U.S. Equity ETF
0.29%
0.02%
0.31%(12)
PIMCO RAFI ESG U.S. ETF
0.29%
0.01%
0.30%
PIMCO Real Return Fund
0.45%
0.08%
0.53%
PIMCO RealEstateRealReturn Strategy Fund
0.74%
1.36%
2.10%
PIMCO Short Asset Investment Fund
0.34%
0.02%
0.36%
PIMCO Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Short Term Municipal Bond Active Exchange-Traded Fund
0.35%
0.00%
0.35%
PIMCO Short-Term Fund
0.45%
0.10%
0.55%
PIMCO StocksPLUS® Absolute Return Fund
0.64%
0.08%
0.72%
PIMCO StocksPLUS® Fund
0.50%
0.06%
0.56%
PIMCO StocksPLUS® International Fund (U.S. Dollar-Hedged)
0.75%
0.25%
1.00%
PIMCO StocksPLUS® International Fund (Unhedged)
0.64%
0.38%
1.02%
PIMCO StocksPLUS® Long Duration Fund
0.59%
0.42%
1.01%
PIMCO StocksPLUS® Short Fund
0.64%
0.45%
1.09%
PIMCO StocksPLUS® Small Fund
0.69%
0.06%
0.75%
PIMCO Strategic Bond Fund
0.55%
0.02%
0.57%(13)
PIMCO Total Return ESG Fund
0.50%
0.46%
0.96%
PIMCO Total Return Fund
0.46%
0.24%
0.70%
PIMCO Total Return Fund II
0.50%
0.26%
0.76%
PIMCO Total Return Fund IV
0.50%
0.30%
0.80%
PIMCO TRENDS Managed Futures Strategy Fund
1.40%
0.29%
1.69%(14)
1
“Management Fees” reflects an advisory fee and a supervisory and administrative fee payable by an Underlying PIMCO Fund to PIMCO.
2
Other Expenses include expenses such as organizational expenses, interest expense, taxes, governmental fees, pro rata Trustees' fees and acquired fund fees and expenses attributable to the Institutional Class or Class M shares or the Fund in the case of exchange-traded funds of the PIMCO ETF Trust or PIMCO Equity Series.
3
PIMCO has contractually agreed, through July 31, 2021, to waive a portion of the Fund’s supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Funds at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided certain conditions are met.
4
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund III Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
5
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund I Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
6
PIMCO has contractually agreed, through October 31, 2021, to waive a portion of the Fund's supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund's organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Equity Series at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
7
PIMCO has contractually agreed, through October 31, 2022, to reduce its management fee by 0.12% of the average daily net assets of the Fund. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO ETF Trust at least 30 days prior to the end of the then current term. In any month in which the investment

April 30, 2021 | PROSPECTUS  23

PIMCO Variable Insurance Trust

management agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the management fee waived as set forth above during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
8
PIMCO has contractually agreed, through July 31, 2022, to waive a portion of the Fund’s supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
9
To maintain certain net yields for the Fund, PIMCO or its affiliates may temporarily and voluntarily waive, reduce or reimburse all or any portion of the Fund's fees and expenses.
10
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund.
11
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Capital Securities Fund (Cayman) Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
12
PIMCO has contractually agreed, through October 31, 2021, to waive a portion of the Fund’s management fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Equity Series at least 30 days prior to the end of the then current term. In any month in which the investment management agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the management fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
13
PIMCO has contractually agreed, through July 31, 2021, to reduce its supervisory and administrative fee for each share class of the Fund by 0.05% of the average daily net assets attributable to the applicable class of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years from the date of waiver.
14
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund VIII, Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO All Asset
Robert D. Arnott
4/03*
Chairman and Founder, Research Affiliates, since July 2002. Previously, Mr. Arnott was
Chairman of First Quadrant, L.P. until April 2004. He first joined First Quadrant in April
1998.
PIMCO All Asset
Christopher J. Brightman
11/16
Chief Investment Officer, Research Affiliates, since April 2014. Previously at Research
Affiliates, Mr. Brightman served as a Managing Director and Head of Investment
Management. Prior to joining Research Affiliates in 2010, Mr. Brightman was chief
executive officer of the University of Virginia Investment Management Company.
*
Inception of the Portfolio.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.

24  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

April 30, 2021 | PROSPECTUS  25

PIMCO Variable Insurance Trust

Class M Shares
The Trust offers investors Class M shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Class M shares.
Distribution and/or Service (12b-1) Fees – Class M Shares. The Trust has adopted a Distribution and Servicing Plan for the Class M shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the 1940 Act. The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Class M shares and/or certain shareholder services to Class M shareholders at an annual rate of up to 0.25% of the Portfolio’s average daily net assets attributable to its Class M shares (the “Distribution Fee”).
The Distribution and Servicing Plan also permits the Portfolio to compensate the Distributor for providing or procuring administrative, recordkeeping, and other investor services at an annual rate with respect to the Portfolio not to exceed 0.20% of the average daily net assets of the Portfolio attributable to Class M shares (the “Servicing Fee”).
Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio’s Class M assets on an ongoing basis, over time they will increase the cost of an investment in Class M shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements. Class M shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Class M shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support
services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to

26  Prospectus | PIMCO Variable Insurance Trust

Prospectus

insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase

April 30, 2021 | PROSPECTUS  27

PIMCO Variable Insurance Trust

of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Underlying PIMCO Funds’ investment strategies may expose such Underlying PIMCO Funds to risks associated with market timing activities. For example, since some Underlying PIMCO Funds may invest in non-U.S. securities, they may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of an Underlying PIMCO Fund’s non-U.S. portfolio securities and the determination of the Underlying PIMCO Fund’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling fund shares at a price that does not reflect their true value. A similar risk exists for an Underlying PIMCO Fund’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
Except as identified below, to discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders (“Market Timing Policy”). Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders. In addition, purchases and sales by the Portfolio in certain Underlying PIMCO Funds may be exempt from certain limitations under the Market Timing Policy in order to allow the Portfolio to manage its cash flows and reallocate portfolio investments in the Underlying PIMCO Funds according to its allocation targets.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or

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refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio and Underlying PIMCO Fund shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or an Underlying PIMCO Fund or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
The assets of the Portfolio consist of shares of the Underlying PIMCO Funds, which are valued at their respective NAVs at the time of valuation of the Portfolio’s shares. For purposes of calculating the NAV of the Underlying PIMCO Funds, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services,
quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of an Underlying PIMCO Fund’s assets that are invested in one or more open-end management investment companies, (other than exchange-traded funds), the Underlying PIMCO Fund’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity

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securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of an Underlying PIMCO Fund’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio invests in Underlying PIMCO Funds that hold foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Trustees or persons acting at their direction. The Trustees has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO.
Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of an Underlying PIMCO Fund’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of
the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When an Underlying PIMCO Fund uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board of Trustees or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s and Underlying PIMCO Funds’ NAVs that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Underlying PIMCO Fund could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by an Underlying PIMCO Fund may differ from the value that would be realized if the securities were sold. An Underlying PIMCO Fund’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.

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Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.The Portfolio may invest in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund. One of the requirements for favorable tax treatment as a regulated investment company under the Code is that each Underlying PIMCO Fund derive at least 90% of its gross income from certain qualifying sources of income. The IRS has issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. As such, each Underlying PIMCO Fund’s ability to utilize commodity-linked swaps as part of its investment strategy is limited to a maximum of 10 percent of its gross income.
However, in a subsequent revenue ruling, the IRS provides that income from alternative investment instruments (such as certain commodity index-linked notes) that create commodity exposure may be considered qualifying income under the Code. The IRS has also issued a private letter ruling to the Underlying PIMCO Funds in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued another private letter ruling to each Underlying PIMCO Fund in which the IRS specifically concluded that income derived from the Underlying PIMCO Fund’s investment in its Subsidiary will also constitute qualifying income to the Underlying PIMCO Fund, even if the Subsidiary itself owns commodity linked swaps. Each Underlying PIMCO Fund will continue to seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in its Subsidiary.
Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if an Underlying PIMCO Fund‘s income from an investment in the subsidiary is derived with respect to the Underlying PIMCO Fund’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the 1940 Act. In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings. There can be no assurance that the IRS will not change its position with respect to some or all of these conclusions or that future legislation will not adversely impact the tax treatment of each Underlying PIMCO Fund’s commodity-linked investments. If the IRS were to change or reverse its position, or if future legislation adversely affected the tax treatment of the commodity-linked investments of each Underlying PIMCO Fund, there would likely be a significant adverse impact on the Underlying
PIMCO Fund, including the possibility of failing to qualify as a regulated investment company. If an Underlying PIMCO Fund did not qualify as a regulated investment company for any taxable year, its taxable income would be subject to tax at the Underlying PIMCO Fund level at regular corporate tax rates (without reduction for distributions to shareholders) and to a further tax at the shareholder level when such income is distributed.
Furthermore, the tax treatment of commodity-linked notes, other commodity-linked derivatives, and an Underlying PIMCO Fund’s investments in its Subsidiary may otherwise be adversely affected by future legislation, court decisions, Treasury Regulations and/or guidance issued by the IRS. Such developments could affect the character, timing and/or amount of the Underlying PIMCO Fund’s taxable income or any distributions made by the Underlying PIMCO Fund or result in the inability of the Underlying PIMCO Fund to operate as described in its prospectus.
A Note on the PIMCO CommodityRealReturn Strategy Fund®, an Underlying PIMCO Fund.Periodic adjustments for inflation to the principal amount of an inflation-indexed bond may give rise to original issue discount, which will be includable in the Underlying PIMCO Fund’s gross income. Due to original issue discount, the Underlying PIMCO Fund may be required to make annual distributions to shareholders that exceed the cash received, which may cause the Underlying PIMCO Fund to liquidate certain investments when it is not advantageous to do so. Also, if the principal value of an inflation-indexed bond is adjusted downward due to deflation, amounts previously distributed in the taxable year may be characterized in some circumstances as a return of capital.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
The Portfolio invests substantially all of its assets in shares of the Underlying PIMCO Funds, and as such (unless otherwise noted) does not invest directly in the securities described below. The Underlying PIMCO Funds, however, may invest in such securities. Because the value of an investment in the Portfolio is directly related to the investment performance of the Underlying PIMCO Funds in which it invests, the risks of investing in the Portfolio are closely related to the risks associated with the Underlying PIMCO Funds and their investments in the securities described below. Please see the “Descriptions of the Underlying PIMCO Funds.”
This section provides additional information about some of the principal investments and related risks of the Portfolio and the Underlying PIMCO Funds described under the “Portfolio Summary,” “Description of Principal Risks” and “Descriptions of the Underlying PIMCO Funds.” It

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also describes characteristics and risks of additional securities and investment techniques that may be used by the Underlying PIMCO Funds from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Underlying PIMCO Funds. As with any mutual fund, investors in the Underlying PIMCO Funds rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Underlying PIMCO Funds.
Because the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, may each invest a portion of its assets in its respective Subsidiary, each of which may hold some of the investments described in this prospectus, each Underlying PIMCO Fund, and to the extent the Portfolio invests in each Underlying PIMCO Fund, the Portfolio, may be indirectly exposed to the risks associated with those investments. With respect to its investments, each Subsidiary will generally be subject to the same fundamental, non-fundamental and certain other investment restrictions as the respective Underlying PIMCO Fund; however, each Subsidiary (unlike the Underlying PIMCO Fund) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. Each Underlying PIMCO Fund and each Subsidiary may test for compliance with certain investment restrictions on a consolidated basis, except that with respect to its investments in certain securities that may involve leverage, the Subsidiary will comply with asset segregation or “earmarking” requirements to the same extent as its respective Underlying PIMCO Fund.
Investors should be aware that the investments made by a Portfolio and the results achieved by a Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to a Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact a Portfolio’s portfolio management. For example, a Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause Portfolios to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase a Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause a Portfolio to perform differently than intended.
Similarly, significant shareholder purchases may adversely affect a Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
Most of the Underlying PIMCO Funds seek maximum total return. The total return sought by an Underlying PIMCO Fund consists of both income earned on the Underlying PIMCO Fund’s investments and capital appreciation, if any, arising from increases in the market value of the Underlying PIMCO Fund’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation or improving credit fundamentals for a particular market sector or security.
In selecting securities for an Underlying PIMCO Fund, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Underlying PIMCO Fund’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income

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Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example,
the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate

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collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Underlying PIMCO Fund to sell its bonds at attractive pries or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolios may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Underlying PIMCO Funds may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Underlying PIMCO Funds may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Underlying PIMCO Funds is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account
securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Underlying PIMCO Funds may subject the Underlying PIMCO Funds to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if an Underlying PIMCO Fund sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
Certain Underlying PIMCO Funds may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that an Underlying PIMCO Fund investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.

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Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose an Underlying PIMCO Fund to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The value of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk.Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect an Underlying PIMCO Fund’s returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Underlying PIMCO Funds may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk.Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Underlying PIMCO Funds to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of
principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on an Underlying PIMCO Fund’s yield to maturity from these securities. Certain Underlying PIMCO Funds may invest up to 5% of their total assets in any combination of mortgage-related or other asset backed IO, PO or inverse floater securities.
An Underlying PIMCO Fund may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties.
Loan Participations and Assignments
Certain Underlying PIMCO Funds may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If an Underlying PIMCO Fund purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
An Underlying PIMCO Fund may be subject to the risk that the returns of the Underlying PIMCO Fund will decline during periods of falling interest rates because the Underlying PIMCO Fund may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Underlying PIMCO Fund’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Underlying PIMCO Fund to invest in lower-yielding securities. An Underlying PIMCO Fund also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Underlying PIMCO Fund’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by an Underlying PIMCO Fund from its investments is likely to have an adverse effect on the Underlying PIMCO Fund’s NAV, yield and total return.

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Focused Investment
To the extent that an Underlying PIMCO Fund focuses its investments in a particular sector, the Underlying PIMCO Fund may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, an Underlying PIMCO Fund may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Underlying PIMCO Fund to greater risk. An Underlying PIMCO Fund also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. Certain Underlying PIMCO Funds may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case an Underlying
PIMCO Fund may lose its entire investment. The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which an Underlying PIMCO Fund may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. Each Underlying PIMCO Fund may invest in floating rate debt instruments (“floaters”) and certain Underlying PIMCO Funds may engage in credit spread trades. . A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Certain Underlying PIMCO Funds may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. Underlying PIMCO Funds that may invest in these securities may invest up to 5% of their total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, certain Underlying PIMCO Funds may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in

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the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Volatility
Volatility measures the variability in the price of an investment over time. A higher volatility level signifies an investment’s value may fluctuate over a larger range within a short period of time, either up or down. A lower volatility level means an investment’s value is more likely to change within a narrower range, or less frequently, over time. The more volatile the portfolio holdings of the Portfolio, the less predictable the returns for the Portfolio. Higher volatility levels may indicate heightened risk of losses.
PIMCO’s use of investments in seeking to manage the Portfolio‘s volatility will be consistent with the Portfolio’s asset allocation guidelines. Although asset allocation cannot eliminate investment risk or losses, it may provide opportunities to manage a Portfolio’s volatility relative to a Portfolio’s target annualized volatility level.
Event-Linked Exposure
Certain Underlying PIMCO Funds may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to
defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, an Underlying PIMCO Fund may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposures may also expose an Underlying PIMCO Fund to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposures may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
Certain Underlying PIMCO Funds may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. An Underlying PIMCO Fund may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Underlying PIMCO Fund’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy

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common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. An Underlying PIMCO Fund may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, an Underlying PIMCO Fund may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for an Underlying PIMCO Fund.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time. In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to an Underlying PIMCO Fund as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, an Underlying PIMCO Fund may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, certain Underlying PIMCO Funds may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by an Underlying PIMCO Fund at any given time upon sale thereof, an Underlying PIMCO Fund may determine to hold such securities in its portfolio.
While certain Underlying PIMCO Funds will generally invest in equity derivatives and will not normally invest directly in equity securities, each such Underlying PIMCO Fund may invest without limit directly in equity securities, including common stocks, preferred securities and convertible securities. In addition, the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, each an Underlying PIMCO Fund, may invest in equity securities of issuers in commodity-related industries, and the PIMCO RealEstateRealReturn Strategy Fund, an Underlying PIMCO Fund, may invest in REITs and equity securities of issuers in real estate-related industries. When investing directly in equity securities, an Underlying PIMCO Fund will not be limited to only those equity securities with any particular weighting in such Underlying PIMCO Fund’s respective benchmark index, if any. Generally, the Underlying PIMCO Funds will consider investing directly in equity securities when derivatives on the underlying securities appear to be overvalued.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by an Underlying PIMCO Fund may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
Certain Underlying PIMCO Funds may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a

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non-U.S. country if the issuer of such money market instrument is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, if the issuer of such money market instrument is organized under the laws of a non-U.S. country, or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Underlying PIMCO Funds that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruption, the possibility of security suspensions and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries’ financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on
those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers' financial reporting.
Certain of the Underlying PIMCO Funds also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.Certain Underlying PIMCO Funds may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries within the limitations, if any, set forth in each Underlying PIMCO Fund’s prospectus. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors, and the order in which they are applied may change in the discretion of PIMCO. The current factors listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of

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the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, an Underlying PIMCO Fund emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by an Underlying PIMCO Fund. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause an Underlying PIMCO Fund to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which an Underlying PIMCO Fund’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Underlying PIMCO Fund.
Foreign Currency Transactions.Underlying PIMCO Funds that invest in securities denominated in foreign (non-U.S.) currencies may engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Underlying PIMCO Fund’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Underlying PIMCO Fund is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Underlying PIMCO Fund’s ability to enter into foreign currency transactions, force the Underlying PIMCO Fund to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Underlying PIMCO Fund, any of which may result in a loss to the Underlying PIMCO Fund. A contract to sell a foreign currency would limit any potential gain which might be realized if the value of the hedged currency increases. An Underlying PIMCO Fund may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that an Underlying PIMCO Fund will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for an Underlying PIMCO Fund to benefit from favorable fluctuations in relevant foreign currencies. An Underlying PIMCO Fund may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of

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currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Underlying PIMCO Fund will segregate or “earmark” assets determined to be liquid by PIMCO in accordance with the procedures established by the Board of Trustees (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of an Underlying PIMCO Fund’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, an Underlying PIMCO Fund’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. An Underlying PIMCO Fund may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if an Underlying PIMCO Fund earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Underlying PIMCO Fund’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio and each Underlying PIMCO Fund may enter into repurchase agreements, in which the Portfolio or the Underlying PIMCO Fund purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s or the Underlying PIMCO Fund’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio or the Underlying PIMCO Fund will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
Each Underlying PIMCO Fund may enter into reverse repurchase agreements and dollar rolls, subject to the Underlying PIMCO Fund’s limitations on borrowings. A reverse repurchase agreement involves the
sale of a security by an Underlying PIMCO Fund and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Underlying PIMCO Fund but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, an Underlying PIMCO Fund will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for an Underlying PIMCO Fund.
The Portfolio and Underlying PIMCO Funds may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio or Underlying PIMCO Fund may borrow money from banks for any purpose in an amount up to 1/3 of the Portfolio’s or Underlying PIMCO Fund’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio or Underlying PIMCO Fund may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s or Underlying PIMCO Fund’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
Certain Underlying PIMCO Funds may, but are not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). An Underlying PIMCO Fund may invest some or all of its assets in derivative instruments, subject to the Underlying PIMCO Fund’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by an Underlying PIMCO Fund will succeed. A description of these and other derivative instruments that the Underlying PIMCO Funds may use are described under “Investment Objectives and Policies” in the SAI.
An Underlying PIMCO Fund’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on an Underlying PIMCO Fund. For example, a small investment in a derivative instrument may have a significant impact on an Underlying PIMCO Fund’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. An Underlying PIMCO Fund may engage in such transactions

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regardless of whether the Underlying PIMCO Fund owns the asset, instrument or components of the index underlying the derivative instrument. An Underlying PIMCO Fund may invest a significant portion of its assets in these types of instruments. If it does, the Underlying PIMCO Fund’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Underlying PIMCO Funds.
CPI Swap. A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk. Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk. The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if an Underlying PIMCO Fund does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk. Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk. Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When an Underlying PIMCO Fund uses derivatives for leverage, investments in
that Underlying PIMCO Fund will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Underlying PIMCO Fund will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability. Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain an Underlying PIMCO Fund’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that an Underlying PIMCO Fund will engage in derivatives transactions at any time or from time to time. An Underlying PIMCO Fund’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk. In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, many of the Underlying PIMCO Funds seek to achieve their investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of these Underlying PIMCO Funds are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent an Underlying PIMCO Fund, or derivatives or other strategies used by the Underlying PIMCO Fund, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Underlying PIMCO Fund and the determination of the NAV value of Underlying PIMCO Fund shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Underlying PIMCO Fund invests; (iv) a fund having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of a fund (due to share purchases or redemptions, for example), potentially resulting in the Underlying PIMCO Fund being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the

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Underlying PIMCO Fund’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks. Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to an Underlying PIMCO Fund’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for an Underlying PIMCO Fund, the Underlying PIMCO Fund might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Underlying PIMCO Fund investments. An Underlying PIMCO Fund may also have to buy or sell a security at a disadvantageous time or price because the Underlying PIMCO Fund is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Underlying PIMCO Fund’s derivative transactions, or impede the employment of the Underlying PIMCO Fund’s derivatives strategies, or adversely affect the Underlying PIMCO Fund’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to an Underlying PIMCO Fund. In addition, an Underlying PIMCO Fund’s use of derivatives may cause the Underlying PIMCO Fund to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Underlying PIMCO Fund had not used such instruments.
A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.The Portfolio may invest in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund. In light of releveant IRS guidance, as discussed above under “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” will seek to gain exposure to the commodity markets primarily through investments in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices, and through investments in its respective Subsidiary (as discussed below). The Underlying
PIMCO Funds may also invest in commodity-linked notes with principal and/or coupon payments linked to the value of particular commodities or commodity futures contracts, or a subset of commodities and commodities futures contracts.
These notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in response to changes in the underlying commodity, commodity futures contract, subset of commodities, subset of commodities futures contracts or commodity index.
These notes expose the Underlying PIMCO Funds economically to movements in commodity prices. These notes also are subject to risks, such as credit, market and interest rate risks, that in general affect the values of debt securities. In addition, these notes are often leveraged, increasing the volatility of each note’s market value relative to changes in the underlying commodity, commodity futures contract or commodity index. Therefore, at the maturity of the note, the Underlying PIMCO Funds may receive more or less principal than it originally invested. The Underlying PIMCO Funds might receive interest payments on the note that are more or less than the stated coupon interest payments.
The Underlying PIMCO Funds may also invest in other commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures. The value of a commodity-linked derivative investment generally is based upon the price movements of a physical commodity (such as energy, mineral, or agricultural products), a commodity futures contract, a subset of commodities, a subset of commodities futures contracts or commodity index, or other economic variable based upon changes in the value of commodities or the commodities markets.
Options transactions may be effected on exchanges or in the OTC market. When OTC options are purchased, an Underlying PIMCO Fund’s portfolio bears the risk that the counterparty that wrote the option will be unable or unwilling to perform its obligations under the option contract. Options may also be illiquid and, in such cases, an Underlying PIMCO Fund may have difficulty closing out its position. OTC options also may include options on baskets of specific securities.
Many swap transactions are privately negotiated agreements between a fund and a counterparty to exchange or swap investment cash flows or assets at specified intervals in the future. The obligations may extend beyond one year. There is often no central exchange for swap transactions and therefore they can be less liquid investments than exchange-traded instruments. The Dodd-Frank Act and related regulatory developments require the clearing and exchange-trading of certain standardized OTC derivative instruments that the CFTC and SEC have defined as “swaps.” The CFTC has implemented mandatory exchange-trading and clearing requirements under the Dodd-Frank Act and the CFTC continues to approve contracts for central clearing. Uncleared swaps are subject to margin requirements that are being implemented on a phased-in basis. The investment adviser will continue to monitor these developments, particularly to the extent regulatory changes affect an Underlying PIMCO Fund’s ability to enter into swap agreements.

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As described below under “Characteristics and Risks of Securities and Investment Techniques-Investments in a Wholly-Owned Subsidiary,” the Underlying PIMCO Funds may gain exposure to commodity markets by investing in their respective Subsidiaries. It is expected that each such Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments.
The IRS issued a revenue ruling that limits the extent to which the Underlying PIMCO Funds may invest directly in commodity-linked swaps or certain other commodity-linked derivatives. The Subsidiaries, on the other hand, may invest in these commodity-linked derivatives generally without limitation. See “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund,” above for further information.
Investments in a Wholly Owned Subsidiary
Investments in the Subsidiaries by the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, are expected to provide the Underlying PIMCO Funds with exposure to the commodity markets within the limitations of Subchapter M of the Code and recent IRS revenue rulings, as discussed above under “Tax Consequences-A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.”
It is expected that each Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation indexed securities and other Fixed Income Instruments. Although the Underlying PIMCO Funds may enter into these commodity-linked derivative instruments directly, the Underlying PIMCO Funds will likely gain exposure to these derivative instruments indirectly by investing in the their respective Subsidiaries. To the extent that PIMCO believes that these commodity-linked derivative instruments are better suited to provide exposure to the commodities market than commodity index-linked notes, each Underlying PIMCO Fund’s investment in its respective Subsidiary will likely increase. Each Subsidiary will also invest in inflation-indexed securities and/or other Fixed Income Instruments, which are intended to serve as margin or collateral for the Subsidiary’s derivatives position, common and preferred securities as well as convertible securities of issuers in commodity-related industries, collateralized debt obligations, event-linked bonds and event-linked swaps. To the extent that an Underlying PIMCO Fund invests in its respective Subsidiary, it may be subject to the risks associated with those derivative instruments and other securities, which are discussed elsewhere in this prospectus.
While each Subsidiary may be considered similar to an investment company, it is not registered under the 1940 Act and, unless otherwise noted in each Underlying PIMCO Fund’s prospectus, is not subject to all
of the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of an Underlying PIMCO Fund and/or a Subsidiary to operate as described in this prospectus and the SAI and could adversely affect an Underlying PIMCO Fund as well as the Portfolio (to the extent the Portfolio invests in an Underlying PIMCO Fund). Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of an Underlying PIMCO Fund and/or a Subsidiary and result in the Underlying PIMCO Fund underperforming its benchmark index(es).
Real Estate Investment Trusts (REITs)
Certain Underlying PIMCO Funds may invest in REITs. REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
Certain Underlying PIMCO Funds may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.

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ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
Certain Underlying PIMCO Funds may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring an Underlying PIMCO Fund to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that an Underlying PIMCO Fund is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
Each Underlying PIMCO Fund may purchase or sell securities which it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Underlying PIMCO Fund’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Underlying PIMCO Fund’s overall investment exposure. Typically, no income accrues on securities that an Underlying PIMCO Fund has committed to purchase prior to the time delivery of the securities is made, although the Underlying PIMCO Fund may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to
a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio invests substantially all of its assets in other investment companies. The Portfolio’s investment in a particular Underlying PIMCO Fund normally will not exceed 50% of its total assets. An Underlying PIMCO Fund may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio and each Underlying PIMCO Fund may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Each Underlying PIMCO Fund may invest in securities of other investment companies, such as closed-end management investment companies including exchange-traded funds, or in pooled accounts or other investment vehicles which to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The limitation described in the foregoing sentence shall not apply to the investments of the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund in the Subsidiaries. As a shareholder of an investment company or other pooled vehicle, the Portfolio or Underlying PIMCO Funds may indirectly bear service and other fees which are in addition to the fees the Portfolio or Underlying PIMCO Funds pays its service providers.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, each Underlying PIMCO Fund may, in the future and the rules and regulations thereunder and any exemptive relief thereform, elect to pursue its investment objective either by investing directly in securities, or by

April 30, 2021 | PROSPECTUS  45

PIMCO Variable Insurance Trust

investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Underlying PIMCO Fund.
Small-Cap and Mid-Cap Companies
Certain Underlying PIMCO Funds may invest in equity securities of small-capitalization and mid-capitalization companies, a small-cap company generally considered to be a company with a market capitalization of up to $1.5 billion and a mid-cap company generally considered to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Underlying PIMCO Fund’s investments in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
Each Underlying PIMCO Fund may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose an Underlying PIMCO Fund to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Underlying PIMCO Fund. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”), the Underlying PIMCO Fund must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that an Underlying PIMCO Fund contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. An Underlying PIMCO Fund may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent an Underlying PIMCO Fund engages in short selling in foreign (non-U.S.) jurisdictions, the Underlying PIMCO Fund will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
Each Underlying PIMCO Fund may invest up to 15% of its net assets (5% of total assets in the case of the PIMCO Government Money Market Fund) (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments, and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term
“illiquid investments” for this purpose means investments that an Underlying PIMCO Fund reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by an Underlying PIMCO Fund in a liquidity category other than “illiquid” pursuant to the Underlying PIMCO Fund’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, each Underlying PIMCO Fund may lend its portfolio securities to brokers, dealers, and other financial institutions provided a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When an Underlying PIMCO Fund lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Underlying PIMCO Fund will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. An Underlying PIMCO Fund may pay lending fees to a party arranging the loan. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time an Underlying PIMCO Fund has held a particular security is not generally a consideration in investment decisions. A change in the securities held by an Underlying PIMCO Fund is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, an Underlying PIMCO Fund may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Underlying PIMCO Fund’s portfolio) involves correspondingly greater expenses to an Underlying PIMCO Fund, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect an Underlying PIMCO Fund’s performance. Please see

46  Prospectus | PIMCO Variable Insurance Trust

Prospectus

the Portfolio’s “Portfolio Summary – Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio and each Underlying PIMCO Fund may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities, in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio or Underlying PIMCO Fund engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s or an Underlying PIMCO Fund’s total net assets may be uninvested. In such cases, Portfolio or Underlying PIMCO Fund assets will be held in cash in the Portfolio’s or Underlying PIMCO Fund’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objectives of the Portfolio and certain Underlying PIMCO Funds are fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval. The investment objectives of certain Underlying PIMCO Funds may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio and Underlying PIMCO Fund investments listed in this prospectus will apply at the time of investment. The Portfolio and each Underlying PIMCO Fund would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. Certain Underlying PIMCO Funds have adopted a policy to invest at least 80% of their assets in investments suggested by their name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. An Underlying PIMCO Fund will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments
held by an Underlying PIMCO Fund could receive a higher rating or a lower rating during the period in which they are held by an Underlying PIMCO Fund. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
An Underlying PIMCO Fund may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Underlying PIMCO Fund may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that a portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Underlying PIMCO Fund invests in high yield and/or unrated securities, the Underlying PIMCO Fund’s success in achieving its investment objective may depend more heavily on the portfolio managers’ creditworthiness analysis than if the Underlying PIMCO Fund invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Underlying PIMCO Funds may invest in other types of securities and use a variety of investment techniques and strategies which are not described in this prospectus. These securities and techniques may subject the Underlying PIMCO Funds to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Underlying PIMCO Funds.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, sub-advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading

April 30, 2021 | PROSPECTUS  47

PIMCO Variable Insurance Trust

counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

48  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Descriptions of the Underlying PIMCO Funds
The Portfolio invests substantially all of its assets in some or all of the Underlying PIMCO Funds, which is defined to include the least expensive class of shares of any actively managed or smart beta funds (including mutual funds or exchange-traded funds) of PIMCO Funds, PIMCO ETF Trust or PIMCO Equity Series, each an affiliated open-end investment company, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. Shares of the PIMCO All Asset: Multi-Real Fund, PIMCO All Asset: Multi-RAE PLUS Fund and PIMCO All Asset: Multi-Short PLUS Fund (the “PAPS All Asset Funds”) may be purchased only by the Portfolio, as well as by the PIMCO All Asset Fund and PIMCO All Asset All Authority Fund, each a series of PIMCO Funds, an affiliated investment company. Because the Underlying PIMCO Funds are not offered in this prospectus, the following provides a general description of the main investments and other information about the Underlying PIMCO Funds. At the discretion of PIMCO and without shareholder approval, the Portfolio may invest in additional Underlying PIMCO Funds created in the future. For a complete description of an Underlying PIMCO Fund, please see that Fund’s Institutional Class or Class M prospectus (or Fund prospectus in the case of any exchange-traded fund of the PIMCO ETF Trust or PIMCO Equity Series, or Fund offering memorandum in the case of the PAPS All Asset Funds), which is incorporated herein by reference and is available free of charge by telephoning 1-800-927-4648.
Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Short Duration
PIMCO Low Duration Income
Short maturity fixed income instruments
0 to 3 years
Max 30% of total
assets below Baa(3)
No Limitation(4)
PIMCO Short Asset Investment
Money market instruments and short maturity
fixed income instruments
≤ 1.5 years
Baa to Aaa
0%
PIMCO Short-Term
Money market instruments and short maturity
fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below Baa
0-10% of total
assets(5)
PIMCO Low Duration
Short maturity fixed income instruments
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration II
Short maturity fixed income instruments with
quality and non-U.S. issuer restrictions
1 to 3 years
A to Aaa
0%
PIMCO Low Duration ESG
Short maturity fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration Credit(10)
Diversified portfolio of fixed income
instruments
0 to 3 years
Max 10% of total
assets below Caa
0-25% of total
assets(11)
Intermediate
Duration
PIMCO Moderate Duration
Short and intermediate maturity fixed income
instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO GNMA and Government
Securities
Short and intermediate maturity
mortgage-related fixed income securities issued
by the Government National Mortgage
Association and U.S. government securities
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa
0%
PIMCO High Yield
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(6); max
20% of total assets
Caa or below
0-20% of total
assets(5)
PIMCO High Yield Spectrum
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(7)
No Limitation(8)
PIMCO Mortgage-Backed Securities
Short and intermediate maturity
mortgage-related fixed income instruments
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa(9)
0%
PIMCO Total Return
Intermediate maturity fixed income instruments
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return II
Intermediate maturity fixed income instruments
with quality and non-U.S. issuer restrictions
+/-2 years of its
benchmark
Baa to Aaa
0%
PIMCO Total Return ESG
Intermediate maturity fixed income instruments
with prohibitions on firms engaged in socially
sensitive practices
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return IV
Intermediate maturity fixed income instruments
+/-1.5 years of its
benchmark
Baa to Aaa
0-15% of total
assets(11)
PIMCO Investment Grade Credit Bond
Investment grade fixed income securities
+/-2 years of its
benchmark
Max 15% of total
assets below Baa
0-30% of total
assets(5)

April 30, 2021 | PROSPECTUS  49

PIMCO Variable Insurance Trust

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Long Duration
PIMCO Long Duration Total Return
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Extended Duration
Long-term maturity fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO Long-Term U.S. Government
Long-term maturity fixed income securities
≥ 8 years
A to Aaa; max 25% Aa;
max 10% A
0%
PIMCO Mortgage Opportunities and
Bond
Mortgage-related assets and fixed income
instruments
(-1) to 8 years
Max 50% of total
assets below Baa(12)
0%
PIMCO Long-Term Credit Bond
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
B to Aaa; max 20% of
total assets below Baa
0-30% of total
assets(5)
Income
PIMCO ESG Income
Broad range of fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Income
Broad range of fixed income instruments
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Preferred and Capital Securities
Capital securities and preferred securities
+/-2 years of its
benchmark
No Limitation
No Limitation(4)
Inflation-Related
PIMCO Real Return
Inflation-indexed fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO Long-Term Real Return
Inflation-indexed fixed income securities
+/-4 years of its
benchmark
B to Aaa; max 20% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO CommoditiesPLUS® Strategy
Commodity-linked derivative instruments
backed by an actively managed low volatility
portfolio of fixed income instruments
≤ 1 year
Max 10% of total
assets below Baa
0-20%(4)
PIMCO CommodityRealReturn Strategy®
Commodity-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO RealEstateRealReturn Strategy
Real estate-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO All Asset: Multi-Real
Derivatives linked to real assets complemented
by a portfolio of inflation-linked securities and
other Fixed Income Instruments
≤ 10 years
B to Aaa; max 20%
below Baa(14)
0-30% of total
assets with respect
to the Fund’s
investments in
Fixed Income
Instruments(15)
Tax Exempt
PIMCO California Short Duration
Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal and California
income tax)
≤ 3 years
Caa to Aaa; max 10%
of total assets below
Baa
0%
PIMCO California Municipal Bond
Municipal securities (exempt from federal and
California income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO Short Duration Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal income tax)
≤ 3 years
Baa to Aaa
0%
PIMCO California Intermediate Municipal
Bond
Intermediate maturity municipal securities
(exempt from federal and California income
tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO National Intermediate Municipal
Bond
Municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO New York Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal and New York
income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO High Yield Municipal Bond
Intermediate to long-term maturity high yield
municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
No Limitation
0%

50  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
PIMCO Emerging Markets Bond
Emerging market fixed income instruments
+/- 2 years of its
benchmark
Max 15% of total
assets below B
≥ 80% of assets(16)
PIMCO Emerging Markets Currency and
Short-Term Investments
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and short-term investments
≤ 2 years
Max 15% of total
assets below B
No Limitation(17)
PIMCO International Bond
(U.S. Dollar-Hedged)
Intermediate maturity hedged non-U.S. fixed
income instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO International Bond (Unhedged)
Intermediate maturity non-U.S. fixed income
instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation
PIMCO Global Advantage® Strategy
Bond
U.S. and non-U.S. fixed income instruments
≤ 8 years
Max 15% of total
assets below B
No Limitation
PIMCO Global Bond Opportunities
(U.S. Dollar-Hedged)
U.S. and hedged non-U.S. intermediate maturity
fixed income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO Global Bond Opportunities
(Unhedged)
U.S. and non-U.S. intermediate maturity fixed
income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation
PIMCO Diversified Income
Investment grade corporate, high yield and
emerging market fixed income instruments
3 to 8 years
Max 10% below B
No Limitation
PIMCO Emerging Markets Local Currency
and Bond
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and fixed income instruments
+/-2 years of its
benchmark
Max 15% of total
assets below B
No Limitation(18)
PIMCO Emerging Markets Corporate
Bond
Diversified portfolio of fixed income
instruments economically tied to emerging
market countries
+/- 2 years of its
benchmark
Max 15% of total
assets below B
No Limitation
Absolute Return
PIMCO Dynamic Bond
Diversified portfolio of fixed income
instruments
(-3) to 8 years
Max 40% of total
assets below Baa
No Limitation(19)
PIMCO Strategic Bond
Diversified portfolio of fixed income
instruments
(-1) to 5 years
Max 20% of total
assets below Baa
No Limitation(20)
PIMCO Credit Opportunities Bond
Diversified portfolio of fixed income
instruments
0 to 6 years
Max 50% of total
assets below B-
No Limitation(5)
PIMCO TRENDS Managed Futures
Strategy
Financial and commodity-linked derivative
instruments selected by a quantitative strategy
and generally backed by a short to intermediate
duration portfolio which may consist of cash
equivalent securities and fixed income
instruments
N/A
No Limitation
No Limitation
PIMCO RAE Fundamental Advantage
PLUS
Long exposure to RAE US Large Model
Portfolio, short exposure to the S&P 500 Index,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO Climate Bond
Diversified portfolio of fixed income
instruments
2 to 8 years
Max 25% of total
assets below Baa
No Limitation(5)

April 30, 2021 | PROSPECTUS  51

PIMCO Variable Insurance Trust

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Domestic
Equity-Related
PIMCO RAE PLUS
Exposure to RAE US Large Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO StocksPLUS® Small
Russell 2000® Index derivatives backed by a
diversified portfolio of actively managed fixed
income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(21)
PIMCO StocksPLUS® Long Duration
S&P 500 Index derivatives backed by a
diversified portfolio of long-term fixed income
instruments
+/-2 years of
Bloomberg
Barclays
Long-Term
Government/Credit
Index(22)
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO StocksPLUS® Absolute Return
S&P 500 Index derivatives backed by a portfolio
of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS®
S&P 500 Index derivatives backed by a portfolio
of short-term fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO RAE PLUS Small
Exposure to RAE US Small Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE US
Exposure to RAE US Portfolio
N/A
N/A
0%
PIMCO RAE US Small
Exposure to RAE US Small Portfolio
N/A
N/A
0%
PIMCO RAFI ESG U.S. ETF
Component Securities of the RAFI ESG US Index
N/A
N/A
0%
PIMCO RAFI Dynamic Multi-Factor
U.S. Equity ETF
Component Securities of the RAFI Dynamic
multi-Factor US Index
N/A
N/A
0%
Equity-Related
PIMCO All Asset: Multi-RAE PLUS
Long exposure to a portfolio of stocks
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below Baa
(14)
No Limitation(21)
International
Equity-Related
PIMCO Dividend and Income
Exposure to RAE Income Global Portfolio in
Equity Sleeve; remainder of portfolio invests in
fixed income instruments of varying maturities
N/A
No Limitation
No Limitation
PIMCO RAE PLUS EMG
Exposure to RAE Emerging Markets Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(21)
PIMCO StocksPLUS® International
(Unhedged)
Non-U.S. equity derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(21)
PIMCO StocksPLUS® International
(U.S. Dollar-Hedged)
Non-U.S. equity derivatives (hedged to
U.S. dollars) backed by a portfolio of fixed
income instruments.
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(21)
PIMCO RAE PLUS International
Exposure to RAE International Large Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(11)
PIMCO RAE Worldwide Long/Short PLUS
Long exposure to RAE Low Volatility U.S. Model
Portfolio, RAE Low Volatility Intl Model Portfolio
and RAE Low Volatility EMG Model Portfolio,
short exposure to certain traditional
capitalization-weighted equity indexes,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(11)
PIMCO RAE Emerging Markets
Exposure to RAE Emerging Markets Portfolio
N/A
N/A
No Limitation
PIMCO RAE International
Exposure to RAE International Portfolio
N/A
N/A
No Limitation
PIMCO RAFI Dynamic Multi-Factor
Emerging Markets Equity ETF
Component securities of the RAFI Dynamic
Multi-Factor Emerging Markets Index
N/A
N/A
No Limitation
PIMCO RAFI Dynamic Multi-Factor
International Equity ETF
Component securities of the RAFI Dynamic
Multi-Factor Developed Ex-U.S. Index
N/A
N/A
No Limitation
U.S. Government
Securities
PIMCO Government Money Market
U.S. government securities
≤ 60 days
dollar-weighted
average maturity
Min 97% of total
assets Prime 1; ≤ 3%
of total assets Prime 2
0%

52  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Short Strategies
PIMCO StocksPLUS® Short
Short S&P 500 Index derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO All Asset: Multi-Short PLUS
Short exposure to equity markets
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below Baa
(14)
No Limitation(21)
Actively-Managed
Exchange-Traded
Funds
PIMCO Active Bond Exchange-Traded
Fixed income instruments of varying maturities
2 to 8 years
Max 30% of total
assets below Baa
0-15% of total
assets(4)
PIMCO Enhanced Low Duration Active
Exchange-Traded
Fixed income instruments of varying maturities
1 to 3 years
Max 15% below Baa
No Limitation(11)
PIMCO Enhanced Short Maturity Active
Exchange-Traded
Short to intermediate maturity fixed income
instruments
≤1 year
Baa to Aaa
0%
PIMCO Intermediate Municipal Bond
Active Exchange-Traded
Intermediate maturity municipal securities
(exempt from federal income tax)
(-2) to 4 years of
its benchmark
Baa to Aaa
0%
PIMCO Short Term Municipal Bond Active
Exchange-Traded
Short maturity municipal securities (exempt
from federal income tax)
≤ 3 years
Baa to Aaa
0%
PIMCO Enhanced Short Maturity Active
ESG Exchange-Traded
Short to intermediate maturity fixed income
instruments
≤1 year
Baa to Aaa
0-10% of total
assets
1
As rated by Moody's, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality.
2
Certain Underlying PIMCO Funds may invest beyond these limits in U.S. dollar-denominated instruments of non-U.S. issuers.
3
Such limitation shall not apply to the Fund's investments in mortgage- and asset-backed securities.
4
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 10% of its total assets.
5
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
6
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index.
7
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML Developed Markets High Yield Constrained (USD Hedged) Index.
8
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to within 10% (plus or minus) of the Fund's benchmark's foreign currency exposure.
9
The Fund may also invest up to an additional 5% of its total assets in mortgage-related high yield instruments rated below Baa.
10
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund. Information for the PIMCO Low Duration Credit Fund is effective as of May 3, 2021.
11
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 5% of its total assets.
12
Such limitation shall not apply to the Fund's investments in mortgage-related securities.
13
Within such limitation, the Fund may invest in mortgage-related securities rated below B.
14
Within such limitation, the Fund may invest in mortgage- and asset-backed securities rated below B.
15
With respect to the Fund's fixed income investments, the Fund will normally limit its foreign currency exposure (from non-U.S. dollar denominated securities or currencies) to 20% of its total assets.
16
The percentage limitation relates to Fixed Income Instruments of non-U.S. issuers denominated in any currency.
17
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or in Fixed Income Instruments denominated in the currencies of, emerging market countries, and in short-term investments.
18
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or Fixed Income Instruments denominated in the currencies of, emerging market countries and in Fixed Income Instruments, each of which may be represented by forwards or derivatives such as options, futures contracts or swap agreements.
19
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
20
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 25% of its total assets.
21
With respect to the Fund's fixed income investments, the Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
22
The Bloomberg Barclays Long-Term Government/Credit Index is an unmanaged index of U.S. Government or investment grade credit securities having a maturity of 10 years or more.

April 30, 2021 | PROSPECTUS  53

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Class M shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO All Asset Portfolio
 
 
 
 
Class M
 
 
 
 
 
 
 
 
12/31/2020
$10.99
$0.37
$0.41
$0.78
$(0.48)
$0.00
$0.00
$(0.48)
12/31/2019
10.12
0.31
0.84
1.15
(0.28)
0.00
0.00
(0.28)
12/31/2018
11.04
0.50
(1.11)
(0.61)
(0.31)
0.00
0.00
(0.31)
12/31/2017
10.18
0.46
0.87
1.33
(0.45)
0.00
(0.02)
(0.47)
12/31/2016
9.25
0.19
0.97
1.16
(0.21)
0.00
(0.02)
(0.23)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratios shown do not include expenses of the investment companies in which a Portfolio may invest. See the Fees and Expenses note in the Notes to Financial Statements for more information regarding the expenses and any applicable fee waivers associated with these investments.
(e)
Includes in-kind purchases and sales of underlying funds. Please see Investments in Securities, note in the Notes to Financial Statements for more information.

54  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets(d)
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.29
7.74%
$71,618
0.775%
0.875%
0.775%
0.875%
3.57%
(e)141%
10.99
11.44
74,777
0.725
0.875
0.725
0.875
2.88
31
10.12
(5.59)
73,521
0.755
0.875
0.755
0.875
4.62
37
11.04
13.19
75,309
0.775
0.875
0.775
0.875
4.26
40
10.18
12.59
65,033
0.725
0.875
0.725
0.875
1.91
67

April 30, 2021 | PROSPECTUS  55

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1855F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
Active Asset Allocation Portfolio – Total Return Oriented With Tail Risk Hedging
PIMCO Balanced Allocation Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Balanced Allocation Portfolio

Investment Objective
The Portfolio seeks total return which exceeds that of its benchmark.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.71%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses
0.01%
Acquired Fund Fees and Expenses
0.04%
Total Annual Portfolio Operating Expenses(1)
0.91%
Fee Waiver and/or Expense Reimbursement(2)
(0.03%)
Total Annual Portfolio Operating Expenses After Fee Waiver
and/or Expense Reimbursement(3)
0.88%
1
Total Annual Portfolio Operating Expenses do not match the Ratio of Expenses to Average Net Assets Excluding Waivers of the Portfolio, as set forth in the Financial Highlights table of the Portfolio’s prospectus, because the Ratio of Expenses to Average Net Assets Excluding Waivers reflects the operating expenses of the Portfolio and does not include Acquired Fund Fees and Expenses.
2
Pacific Investment Management Company LLC (“PIMCO”) has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, to the extent necessary, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the expenses attributable to the Management Fees of series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust indirectly incurred by the Portfolio in connection with its investments in series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust, to the extent the Portfolio’s advisory fee or advisory fee and supervisory and administrative fee, taken together, are greater than or equal to the Management Fees of the series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust in which the Portfolio invests. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term.
3
“Other Expenses” and Acquired Fund Fees and Expenses include interest expense of the Portfolio and of the series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust in which the Portfolio invests of 0.01% and 0.01%, respectively. Interest expense is borne by the Portfolio and the series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust in which the Portfolio invests separately from the management fees paid to PIMCO. Excluding interest expense of the Portfolio and of the series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust in which the Portfolio invests, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 0.86% for Administrative Class shares.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares
at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$90
$287
$501
$1,117
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 497% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing, under normal circumstances, in equity derivatives and other equity-related investments that provide equity-related exposure equivalent to 50-70% of its net assets (such portion of the Portfolio’s Portfolio, the “Equity Sleeve”) and the remainder of its net assets in a diversified portfolio of Fixed Income Instruments (such portion of the Portfolio’s Portfolio, the “Fixed Income Sleeve”). “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of the Portfolio’s Fixed Income Sleeve normally varies within 1 year (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays U.S. Aggregate Index, as calculated by PIMCO, which as of February 28, 2021 was 6.11 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Equity Sleeve seeks to provide returns that are correlated to the returns of the S&P 500 Index and MSCI Europe Australasia Far East (“EAFE”) Net Dividend Index (USD Unhedged) in proportion to their relative weights in the Portfolio’s benchmark. Within the Equity Sleeve, the Portfolio will invest under normal circumstances in S&P 500 Index derivatives and MSCI EAFE Net Dividend Index (USD Unhedged) derivatives, backed by a portfolio of short-term Fixed Income Instruments. Within the Equity Sleeve, the Portfolio will normally use equity derivatives instead of stocks to attempt to achieve the Portfolio’s investment objective. However, the Portfolio may invest some or all of the net assets attributable to the Equity Sleeve in stocks. The value of equity derivatives should closely track changes in the value of underlying securities or indices. However, derivatives may be purchased with a small fraction of the assets that would be needed to purchase the

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

equity securities directly, so that the remainder of the assets attributable to the Equity Sleeve may be invested in short-term Fixed Income Instruments.
The Fixed Income Sleeve seeks to provide returns that equal or exceed the returns of the Bloomberg Barclays U.S. Aggregate Index. Within the Fixed Income Sleeve, the Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. Within the Fixed Income Sleeve, the Portfolio may invest up to 15% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. Within the Fixed Income Sleeve, the Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 5% of its total assets. Within the Fixed Income Sleeve, the Portfolio may invest up to 5% of its total assets in securities and instruments that are economically tied to emerging market countries.
The Portfolio also may invest in affiliated and unaffiliated exchange-traded funds and mutual funds.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. Within the Fixed Income Sleeve, the Portfolio may invest up to 10% of its total assets in preferred securities. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Small Portfolio Risk:the risk that a smaller Portfolio may not achieve investment or trading efficiencies. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares
Allocation Risk:the risk that a Portfolio could lose money as a result of less than optimal or poor asset allocation decisions. The Portfolio could miss attractive investment opportunities by underweighting markets that subsequently experience significant returns and could lose value by overweighting markets that subsequently experience significant declines
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill

April 30, 2021 | PROSPECTUS  2

PIMCO Balanced Allocation Portfolio

its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to
restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s broad-based securities market index is the 35% S&P 500 Index / 25% MSCI EAFE Index / 40% Bloomberg Barclays U.S. Aggregate Index. The 35% S&P 500 Index / 25% MSCI EAFE Index / 40% Bloomberg Barclays U.S. Aggregate Index is a blended index. The S&P 500 Index is an unmanaged market index generally considered representative of the stock market as a whole. The S&P 500 Index focuses on the large-cap segment of the U.S. equities market. The MSCI

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

EAFE (Morgan Stanley Capital International Europe, Australasia, Far East) Index is a free float-adjusted market capitalization index that is designed to measure the equity market performance of developed markets, excluding the US & Canada. The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable, and dollar denominated. The Bloomberg Barclays U.S. Aggregate Index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
June 30, 2020
12.39%
Worst Quarter
March 31, 2020
-12.81%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Administrative Class Return
11.12%
8.03%
4.63%
4/27/2012
35% S&P 500 Index / 25% MSCI EAFE
Index / 40% Bloomberg Barclays
U.S. Aggregate Index (reflects no
deductions for fees, expenses or taxes)
12.13%
9.21%
8.28%
 
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Erin Browne, Emmanuel Sharef and Rahul Devgon. Ms. Browne is a Managing Director of PIMCO and a senior portfolio manager in the Asset Allocation team. Dr. Sharef is an Executive Vice President of PIMCO. Mr. Devgon is a Senior Vice President of PIMCO. Ms. Browne, Dr. Sharef and Mr. Devgon have jointly and primarily managed the Portfolio since December 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Small Portfolio Risk
A smaller Portfolio may not grow to or maintain an economically viable size to achieve investment or trading efficiencies, which may negatively impact performance and/or force the Portfolio to liquidate. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchases or redemptions.
Allocation Risk
The Portfolio’s investment performance depends upon how its assets are allocated and reallocated according to the Portfolio’s asset allocation targets and ranges. A principal risk of investing in the Portfolio is that PIMCO will make less than optimal or poor asset allocation decisions. PIMCO attempts to identify investment allocations that will provide consistent, quality performance for the Portfolio, but there is no guarantee that such allocation techniques will produce the desired results. It is possible that PIMCO will focus on an investment that performs poorly or underperforms other investments under various market conditions. You could lose money on your investment in the Portfolio as a result of these allocation decisions.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.

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A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the

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Prospectus

Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.

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Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the

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Prospectus

Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities

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are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt

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default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.

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PIMCO Variable Insurance Trust

Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.
Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can

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be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.71% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.66% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.05% (stated as a percentage of the average daily net assets of the Portfolio).
PIMCO has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the expenses attributable to the Management Fees of series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust indirectly incurred by the Portfolio in connection with its investments in series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust to the extent the Portfolio’s Management Fees are greater than or equal to the Management Fees of the series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term.
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not:

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1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Balanced Allocation
Erin Browne
12/19
Managing Director, PIMCO. Ms. Browne is a portfolio manager in the Newport Beach office,
focusing on multi-asset strategies. In her role, she works with PIMCO's asset allocation team
and with portfolio managers across asset classes and sectors globally. Prior to joining PIMCO
in 2018, Ms. Browne was a managing director and head of asset allocation at UBS Asset
Management, helping to drive the firm's macro research, capital market assumptions,
tactical asset allocation and strategic asset allocation views across asset classes. Previously,
she was head of macro investments at UBS O'Connor, a multi-strategy hedge fund manager,
and a global macro portfolio manager at Point72 Asset Management. Ms. Browne has also
held roles at Citigroup, Moore Capital Management and Neuberger Berman, and she began
her career at Lehman Brothers. She has investment experience since 2002 and holds a
bachelor's degree in economics from Georgetown University.
PIMCO Balanced Allocation
Rahul Devgon
12/19
Senior Vice President, PIMCO. Mr. Devgon is a portfolio manager focusing on asset allocation
strategies. Prior to joining PIMCO in 2013, Mr. Devgon was associated with Moore Capital
where he traded global macro assets.
PIMCO Balanced Allocation
Emmanuel Sharef
12/19
Executive Vice President, PIMCO. Dr. Sharef is an executive vice president and portfolio
manager in the Newport Beach office, focused on asset allocation strategies and the
residential real estate market. He is a member of the Americas Portfolio Committee and has
served as a rotating member of the Investment Committee. Prior to joining PIMCO in 2011,
he worked in the mortgage credit strategists group at Morgan Stanley. He has investment
and financial services experience since 2008 and holds a Ph.D. in operations research from
Cornell University, specializing in statistics and biometrics. He received an undergraduate
degree from Princeton University.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

April 30, 2021 | PROSPECTUS  15

PIMCO Variable Insurance Trust

Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the 1940 Act, an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

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conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them

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or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the
Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;

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repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported
by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing

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out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond
the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of

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the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower
characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the

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current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that
are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a

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smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable

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generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.
The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined

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by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,
PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for

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many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign
currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.

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Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with

30  Prospectus | PIMCO Variable Insurance Trust

Prospectus

many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in the Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or
holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the

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PIMCO Variable Insurance Trust

underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment
basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

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Prospectus

Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

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Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolio does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio's financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio's independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Balanced Allocation Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$10.18
$0.04
$0.96
$1.00
$(0.10)
$(0.75)
$0.00
$(0.85)
12/31/2019
8.74
0.17
1.48
1.65
(0.21)
0.00
0.00
(0.21)
12/31/2018
10.73
0.16
(0.73)
(0.57)
(0.13)
(1.29)
0.00
(1.42)
12/31/2017
9.44
0.08
1.28
1.36
(0.07)
0.00
0.00
(0.07)
12/31/2016
9.24
0.13
0.14
0.27
0.00
0.00
(0.07)
(0.07)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratios shown do not include expenses of the investment companies in which the Portfolio may invest. See the Fees and Expenses note in the Notes to Financial Statements for more information regarding the expenses and any applicable fee waivers associated with these investments.
(e)
Effective October 21, 2016, the Portfolio’s Investment advisory fee was decreased by 0.34% to an annual rate of 0.66%.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets(d)
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.33
11.12%
$88,098
0.84%
0.87%
0.83%
0.86%
0.38%
497%
10.18
19.00
91,875
0.91
0.93
0.84
0.86
1.81
534
8.74
(5.59)
86,180
0.92
0.94
0.84
0.86
1.47
435
10.73
14.48
101,361
0.84
0.86
0.84
0.86
0.79
508
9.44
2.94
97,981
1.02(e)
1.15(e)
1.01(e)
1.14(e)
1.43
483

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2055F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
Active Asset Allocation Portfolio – Total Return Oriented With Tail Risk Hedging
PIMCO Balanced Allocation Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Balanced Allocation Portfolio

Investment Objective
The Portfolio seeks total return which exceeds that of its benchmark.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.71%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses
0.01%
Acquired Fund Fees and Expenses
0.04%
Total Annual Portfolio Operating Expenses(1)
1.01%
Fee Waiver and/or Expense Reimbursement(2)
(0.03%)
Total Annual Portfolio Operating Expenses After Fee Waiver and/or
Expense Reimbursement(3)
0.98%
1
Total Annual Portfolio Operating Expenses do not match the Ratio of Expenses to Average Net Assets Excluding Waivers of the Portfolio, as set forth in the Financial Highlights table of the Portfolio’s prospectus, because the Ratio of Expenses to Average Net Assets Excluding Waivers reflects the operating expenses of the Portfolio and does not include Acquired Fund Fees and Expenses.
2
Pacific Investment Management Company LLC (“PIMCO”) has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, to the extent necessary, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the expenses attributable to the Management Fees of series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust indirectly incurred by the Portfolio in connection with its investments in series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust, to the extent the Portfolio’s advisory fee or advisory fee and supervisory and administrative fee, taken together, are greater than or equal to the Management Fees of the series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust in which the Portfolio invests. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term.
3
“Other Expenses” and Acquired Fund Fees and Expenses include interest expense of the Portfolio and of the series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust in which the Portfolio invests of 0.01% and 0.01%, respectively. Interest expense is borne by the Portfolio and the series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust in which the Portfolio invests separately from the management fees paid to PIMCO. Excluding interest expense of the Portfolio and of the series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust in which the Portfolio invests, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 0.96% for Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your
investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$100
$319
$555
$1,234
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 497% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing, under normal circumstances, in equity derivatives and other equity-related investments that provide equity-related exposure equivalent to 50-70% of its net assets (such portion of the Portfolio’s Portfolio, the “Equity Sleeve”) and the remainder of its net assets in a diversified portfolio of Fixed Income Instruments (such portion of the Portfolio’s Portfolio, the “Fixed Income Sleeve”). “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of the Portfolio’s Fixed Income Sleeve normally varies within 1 year (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays U.S. Aggregate Index, as calculated by PIMCO, which as of February 28, 2021 was 6.11 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Equity Sleeve seeks to provide returns that are correlated to the returns of the S&P 500 Index and MSCI Europe Australasia Far East (“EAFE”) Net Dividend Index (USD Unhedged) in proportion to their relative weights in the Portfolio’s benchmark. Within the Equity Sleeve, the Portfolio will invest under normal circumstances in S&P 500 Index derivatives and MSCI EAFE Net Dividend Index (USD Unhedged) derivatives, backed by a portfolio of short-term Fixed Income Instruments. Within the Equity Sleeve, the Portfolio will normally use equity derivatives instead of stocks to attempt to achieve the Portfolio’s investment objective. However, the Portfolio may invest some or all of the net assets attributable to the Equity Sleeve in stocks. The value of equity derivatives should closely track changes in the value of underlying securities or indices. However, derivatives may be purchased with a small fraction of the assets that would be needed to purchase the

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

equity securities directly, so that the remainder of the assets attributable to the Equity Sleeve may be invested in short-term Fixed Income Instruments.
The Fixed Income Sleeve seeks to provide returns that equal or exceed the returns of the Bloomberg Barclays U.S. Aggregate Index. Within the Fixed Income Sleeve, the Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. Within the Fixed Income Sleeve, the Portfolio may invest up to 15% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. Within the Fixed Income Sleeve, the Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 5% of its total assets. Within the Fixed Income Sleeve, the Portfolio may invest up to 5% of its total assets in securities and instruments that are economically tied to emerging market countries.
The Portfolio also may invest in affiliated and unaffiliated exchange-traded funds and mutual funds.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. Within the Fixed Income Sleeve, the Portfolio may invest up to 10% of its total assets in preferred securities. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Small Portfolio Risk:the risk that a smaller Portfolio may not achieve investment or trading efficiencies. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares
Allocation Risk:the risk that a Portfolio could lose money as a result of less than optimal or poor asset allocation decisions. The Portfolio could miss attractive investment opportunities by underweighting markets that subsequently experience significant returns and could lose value by overweighting markets that subsequently experience significant declines
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill

April 30, 2021 | PROSPECTUS  2

PIMCO Balanced Allocation Portfolio

its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to
restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s broad-based securities market index is the 35% S&P 500 Index / 25% MSCI EAFE Index / 40% Bloomberg Barclays U.S. Aggregate Index. The 35% S&P 500 Index / 25% MSCI EAFE Index / 40% Bloomberg Barclays U.S. Aggregate Index is a blended index. The S&P 500 Index is an unmanaged market index generally considered representative of the stock market as a whole. The S&P 500 Index focuses on the large-cap segment of the U.S. equities market. The MSCI

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

EAFE (Morgan Stanley Capital International Europe, Australasia, Far East) Index is a free float-adjusted market capitalization index that is designed to measure the equity market performance of developed markets, excluding the US & Canada. The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable, and dollar denominated. The Bloomberg Barclays U.S. Aggregate Index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
June 30, 2020
12.32%
Worst Quarter
March 31, 2020
-12.84%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Advisor Class Return
10.96%
8.36%
4.61%
4/30/2013
35% S&P 500 Index / 25% MSCI EAFE
Index / 40% Bloomberg Barclays
U.S. Aggregate Index (reflects no
deductions for fees, expenses or taxes)
12.13%
9.21%
7.80%
 
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Erin Browne, Emmanuel Sharef and Rahul Devgon. Ms. Browne is a Managing Director of PIMCO and a senior portfolio manager in the Asset Allocation team. Dr. Sharef is an Executive Vice President of PIMCO. Mr. Devgon is a Senior Vice President of PIMCO. Ms. Browne, Dr. Sharef and Mr. Devgon have jointly and primarily managed the Portfolio since December 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Small Portfolio Risk
A smaller Portfolio may not grow to or maintain an economically viable size to achieve investment or trading efficiencies, which may negatively impact performance and/or force the Portfolio to liquidate. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchases or redemptions.
Allocation Risk
The Portfolio’s investment performance depends upon how its assets are allocated and reallocated according to the Portfolio’s asset allocation targets and ranges. A principal risk of investing in the Portfolio is that PIMCO will make less than optimal or poor asset allocation decisions. PIMCO attempts to identify investment allocations that will provide consistent, quality performance for the Portfolio, but there is no guarantee that such allocation techniques will produce the desired results. It is possible that PIMCO will focus on an investment that performs poorly or underperforms other investments under various market conditions. You could lose money on your investment in the Portfolio as a result of these allocation decisions.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the

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Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.

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Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the

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Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities

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are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt

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default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.

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Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.
Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can

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be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.71% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.66% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.05% (stated as a percentage of the average daily net assets of the Portfolio).
PIMCO has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the expenses attributable to the Management Fees of series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust indirectly incurred by the Portfolio in connection with its investments in series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust to the extent the Portfolio’s Management Fees are greater than or equal to the Management Fees of the series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term.
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not:

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1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Balanced Allocation
Erin Browne
12/19
Managing Director, PIMCO. Ms. Browne is a portfolio manager in the Newport Beach office,
focusing on multi-asset strategies. In her role, she works with PIMCO's asset allocation team
and with portfolio managers across asset classes and sectors globally. Prior to joining PIMCO
in 2018, Ms. Browne was a managing director and head of asset allocation at UBS Asset
Management, helping to drive the firm's macro research, capital market assumptions,
tactical asset allocation and strategic asset allocation views across asset classes. Previously,
she was head of macro investments at UBS O'Connor, a multi-strategy hedge fund manager,
and a global macro portfolio manager at Point72 Asset Management. Ms. Browne has also
held roles at Citigroup, Moore Capital Management and Neuberger Berman, and she began
her career at Lehman Brothers. She has investment experience since 2002 and holds a
bachelor's degree in economics from Georgetown University.
PIMCO Balanced Allocation
Rahul Devgon
12/19
Senior Vice President, PIMCO. Mr. Devgon is a portfolio manager focusing on asset allocation
strategies. Prior to joining PIMCO in 2013, Mr. Devgon was associated with Moore Capital
where he traded global macro assets.
PIMCO Balanced Allocation
Emmanuel Sharef
12/19
Executive Vice President, PIMCO. Dr. Sharef is an executive vice president and portfolio
manager in the Newport Beach office, focused on asset allocation strategies and the
residential real estate market. He is a member of the Americas Portfolio Committee and has
served as a rotating member of the Investment Committee. Prior to joining PIMCO in 2011,
he worked in the mortgage credit strategists group at Morgan Stanley. He has investment
and financial services experience since 2008 and holds a Ph.D. in operations research from
Cornell University, specializing in statistics and biometrics. He received an undergraduate
degree from Princeton University.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

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Prospectus

From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

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circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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PIMCO Variable Insurance Trust

the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;

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bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of
the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be

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adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease
significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an

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obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored
mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the

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current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that
are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a

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smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable

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generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.
The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined

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by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,
PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for

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many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign
currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.

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Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with

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many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or
holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the

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underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment
basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

April 30, 2021 | PROSPECTUS  33

PIMCO Variable Insurance Trust

Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolio does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

34  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Balanced Allocation Portfolio
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$10.40
$0.03
$0.98
$1.01
$(0.09)
$(0.75)
$0.00
$(0.84)
12/31/2019
8.92
0.17
1.51
1.68
(0.20)
0.00
0.00
(0.20)
12/31/2018
10.92
0.15
(0.74)
(0.59)
(0.12)
(1.29)
0.00
(1.41)
12/31/2017
9.61
0.07
1.30
1.37
(0.06)
0.00
0.00
(0.06)
12/31/2016
9.22
0.13
0.33
0.46
0.00
0.00
(0.07)
(0.07)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratios shown do not include expenses of the investment companies in which a Portfolio may invest. See the Fees and Expenses note in the Notes to Financial Statements for more information regarding the expenses and any applicable fee waivers associated with these investments.
(e)
Effective October 21, 2016, the Portfolio’s Investment advisory fee was decreased by 0.34% to an annual rate of 0.66%.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets(d)
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.57
10.96%
$1,235
0.94%
0.97%
0.93%
0.96%
0.27%
497%
10.40
18.95
1,252
1.01
1.03
0.94
0.96
1.71
534
8.92
(5.68)
1,149
1.02
1.04
0.94
0.96
1.36
435
10.92
14.32
1,545
0.94
0.96
0.94
0.96
0.69
508
9.61
4.99
1,409
1.12(e)
1.25(e)
1.11(e)
1.24(e)
1.42
483

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2083F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
Real Return Strategy Portfolio
PIMCO CommodityRealReturn® Strategy Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO CommodityRealReturn® Strategy Portfolio

Investment Objective
The Portfolio seeks maximum real return, consistent with prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.74%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.35%
Acquired Fund Fees and Expenses
0.14%
Total Annual Portfolio Operating Expenses
1.38%
Fee Waiver and/or Expense Reimbursement(2)
(0.14%)
Total Annual Portfolio Operating Expenses After Fee Waiver
and/or Expense Reimbursement
1.24%
1
“Other Expenses” include interest expense of 0.35%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 0.89% for Administrative Class shares.
2
PIMCO has contractually agreed to waive the Portfolio’s advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Portfolio I Ltd. (the “CRRS Subsidiary”) to PIMCO. The CRRS Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO’s contract with the CRRS Subsidiary is in place.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$126
$423
$742
$1,645
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 250% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. “Real Return” equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure. The Portfolio invests in commodity-linked derivative instruments, including swap agreements, futures, options on futures, commodity index-linked notes and commodity options, that provide exposure to the investment returns of the commodities markets, without investing directly in physical commodities. Commodities are assets that have tangible properties, such as oil, metals, and agricultural products. The value of commodity-linked derivative instruments may be affected by overall market movements and other factors affecting the value of a particular industry or commodity, such as weather, disease, embargoes, or political and regulatory developments. The Portfolio may also invest in common and preferred securities as well as convertible securities of issuers in commodity-related industries. When determining the target allocation for the strategy, PIMCO may use proprietary quantitative models. The target allocations may include long, short, or no positions in the underlying financial markets and commodities specified in the models. The quantitative models are developed and maintained by PIMCO, and are subject to change over time without notice in PIMCO’s discretion. PIMCO also retains discretion over the final target asset allocation and the implementation of the target asset allocation, which may include positions that are different from target allocations determined by quantitative models.
The Portfolio will generally seek to gain exposure to the commodity markets primarily through investments in swap agreements, futures, and options on futures and through investments in the PIMCO Cayman Commodity Portfolio I Ltd., a wholly-owned subsidiary of the Portfolio organized under the laws of the Cayman Islands (the “CRRS Subsidiary”). The CRRS Subsidiary is advised by PIMCO, and has the same investment objective as the Portfolio. As discussed in greater detail elsewhere in this prospectus, the CRRS Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. In order to comply with certain issuer diversification limits imposed by the Internal Revenue Code, the Portfolio may invest up to 25% of its total assets in the CRRS Subsidiary.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

The derivative instruments in which the Portfolio and the CRRS Subsidiary primarily intend to invest are instruments linked to certain commodity indices. Additionally, the Portfolio or the CRRS Subsidiary may invest in derivative instruments linked to the value of a particular commodity or commodity futures contract, or a subset of commodities or commodity futures contracts. The Portfolio’s or the CRRS Subsidiary’s investments in commodity-linked derivative instruments may specify exposure to commodity futures with different roll dates, reset dates or contract months than those specified by a particular commodity index. As a result, the commodity-linked derivatives component of the Portfolio’s portfolio may deviate from the returns of any particular commodity index. The Portfolio or the CRRS Subsidiary may over-weight or under-weight its exposure to a particular commodity index, or a subset of commodities, such that the Portfolio has greater or lesser exposure to that index than the value of the Portfolio’s net assets, or greater or lesser exposure to a subset of commodities than is represented by a particular commodity index. Such deviations will frequently be the result of temporary market fluctuations, and under normal circumstances the Portfolio will seek to maintain notional exposure to one or more commodity indices within 5% (plus or minus) of the value of the Portfolio’s net assets.
The Portfolio may also invest in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices. These commodity index-linked notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in response to changes in the underlying commodity or related index of investment.
Assets not invested in commodity-linked derivative instruments or the CRRS Subsidiary may be invested in inflation-indexed securities and other Fixed Income Instruments, including derivative Fixed Income Instruments. In addition, the Portfolio may invest its assets in particular sectors of the commodities market.
The average portfolio duration of the fixed income portion of this Portfolio will vary based on PIMCO’s forecast for interest rates and under normal market conditions is not expected to exceed ten years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest up to 30% of its total assets in securities denominated in foreign currencies and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 10% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year
remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The Portfolio may also invest up to 10% of its total assets in preferred securities. The Portfolio may purchase and sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales.
Principal Risks
It is possible to lose money on an investment in the Portfolio. Under certain conditions, generally in a market where the value of both commodity-linked derivative instruments and fixed income securities are declining, the Portfolio may experience substantial losses. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are:
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services

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Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Model Risk:the risk that the Portfolio’s investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in the Portfolio
Commodity Risk:the risk that investing in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO, including the use of quantitative models or methods, will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Inflation-Indexed Security Risk:the risk that inflation-indexed debt securities are subject to the effects of changes in market interest rates caused by factors other than inflation (real interest rates). In general, the value of an inflation-indexed security, including TIPS, tends to decrease when real interest rates increase and can increase when real interest rates decrease. Interest payments on inflation-indexed securities are unpredictable and will fluctuate as the principal and interest are

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adjusted for inflation. There can be no assurance that the inflation index used will accurately measure the real rate of inflation in the prices of goods and services. Any increase in the principal amount of an inflation-indexed debt security will be considered taxable ordinary income, even though the Portfolio will not receive the principal until maturity
Tax Risk:the risk that the tax treatment of swap agreements and other derivative instruments, such as commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures, may be affected by future regulatory or legislative changes that could affect whether income from such investments is “qualifying income” under Subchapter M of the Internal Revenue Code, or otherwise affect the character, timing and/or amount of the Portfolio’s taxable income or gains and distributions
Subsidiary Risk:the risk that, by investing in the CRRS Subsidiary, the Portfolio is indirectly exposed to the risks associated with the CRRS Subsidiary’s investments. The CRRS Subsidiary is not registered under the 1940 Act and may not be subject to all the investor protections of the 1940 Act. There is no guarantee that the investment objective of the CRRS Subsidiary will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Commodity Index Total Return is an unmanaged index composed of futures contracts on a number of physical commodities. The index is designed to be a highly liquid and diversified benchmark for commodities as an asset class.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
June 30, 2016
13.70%
Worst Quarter
March 31, 2020
-27.08%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Administrative Class Return
1.35%
2.67%
-5.39%
Bloomberg Commodity Index Total Return (reflects no
deductions for fees, expenses or taxes)
-3.12%
1.03%
-6.50%
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Nicholas J. Johnson, Steve Rodosky and Greg Sharenow. Messrs. Johnson, Rodosky and Sharenow are Managing Directors of PIMCO. Mr. Johnson has managed the Portfolio since January 2015, Mr. Rodosky has managed the Portfolio since January 2019 and Mr. Sharenow has managed the Portfolio since November 2018.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

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Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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Prospectus

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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Prospectus

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests. These factors include the possibility that the Portfolio's commodity derivatives positions may have different roll dates, reset dates or contract months than those specified in a particular commodity index.   By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Model Risk
In making investment allocation decisions for the Portfolio PIMCO may utilize quantitative models that may be proprietary or developed by third-parties. These models are used by PIMCO to determine (or assist in determining) the Portfolio’s target asset allocation and to identify potentially attractive relative value and risk hedging strategies. The investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in the Portfolio. There can be no assurance that the models used by PIMCO will remain viable, due to various factors, which may include the quality of the data input into the models and the assumptions underlying such models, which to varying degrees involve the exercise of judgment, as well as the possibility of errors in constructing or using the model.
Models rely on accurate market data inputs. If inaccurate market data is entered into a model, the resulting information will be incorrect. In addition, the models used may be predictive in nature and such models may result in an incorrect assessment of future events. The models evaluate securities or securities markets based on certain assumptions concerning the interplay of market factors. The markets or the prices of individual securities may be affected by factors not foreseen in developing the models. In addition, when relying on a quantitative model and/or data supplied by third parties, PIMCO may have less insight into the construction, coding or testing of the third-party model or data, and PIMCO will be exposed to systems, cyber security and other risks associated with the third party that provides the model or data.
The use of models can be complex and involves financial, economic, econometric and statistical theories, research and modeling; and the results of those processes must then be translated into computer code. Although PIMCO seeks to hire individuals and/or third parties, as applicable, skilled in each of these functions and to provide appropriate levels of oversight, the complexity of the individual tasks, the difficulty of integrating such tasks, and the limited ability to perform “real world” testing of a model’s end product raises the chances that a finished model may contain an error; one or more of such errors could adversely affect the Portfolio’s performance.
Commodity Risk
The Portfolio’s investments in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments. The Portfolio and the CRRS Subsidiary may each concentrate its assets in a particular sector of the commodities market (such as oil, metal or agricultural products). As a result, the Portfolio and the CRRS Subsidiary may be more susceptible to risks associated with those sectors. The prices for commodities in those sectors may fluctuate widely due to factors such as changes in value, supply and demand and governmental regulatory policies.

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Prospectus

Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries

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are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The CRRS Subsidiary will comply with these asset segregation or “earmarking” requirements to the same extent as the Portfolio. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy its obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.

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Prospectus

Management Risk
The Portfolio and the CRRS Subsidiary are subject to management risk because they are actively managed investment portfolios. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis and will, in some cases, rely partially or entirely upon or be informed by one or more quantitative models in making investment decisions for the Portfolio and the CRRS Subsidiary, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio and the CRRS Subsidiary to achieve their investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s and the CRRS Subsidiary’s ability to realize their investment objective. Similarly, there can be no assurance that quantitative models or methods utilized by PIMCO or related data sources will always be available, and the loss of access to any such model(s) or data sources could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Tax Risk
The Portfolio gains exposure to the commodities markets through investments in commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures. The Portfolio may also gain exposure indirectly to commodity markets by investing in the CRRS Subsidiary, which invests primarily in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and/or other Fixed Income Instruments. In order for the Portfolio to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”), the Portfolio must derive at least 90 percent of its gross income each taxable year from certain qualifying sources of income.
As more fully described below under “Tax Consequences-A Note on the Portfolio,” the Internal Revenue Service (the “IRS”) issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. However, the IRS has issued private letter rulings in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued private letter rulings in which the IRS specifically concluded that income derived from an investment in the CRRS Subsidiary will also constitute qualifying income to the Portfolio. Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio’s income from an investment in the subsidiary is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the Investment Company Act of 1940, as amended (the “1940 Act”). In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings.
The Portfolio will seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the CRRS Subsidiary. If the IRS were to determine that income derived from certain commodity-linked notes or from investments in the CRRS Subsidiary does not constitute qualifying income, the Portfolio might be adversely affected and would be required to reduce its exposure to such investments which might result in difficulty in implementing its investment strategies and increased costs and taxes. The use of commodity index-linked notes and investments in the CRRS Subsidiary involve specific risks. See “Characteristics and Risks of Securities and Investment Techniques —Derivatives—A Note on the Portfolio” below for further information regarding commodity index-linked notes, including the risks associated with these instruments. In addition, see “Characteristics and Risks of Securities and Investment Techniques-Investments in the Wholly-Owned Subsidiary” below for further information regarding the CRRS Subsidiary, including the risks associated with investing in the CRRS Subsidiary.
Subsidiary Risk
By investing in the CRRS Subsidiary, the Portfolio is indirectly exposed to the risks associated with the CRRS Subsidiary’s investments. The investments held by the CRRS Subsidiary are generally similar to those that are permitted to be held by the Portfolio and are subject to the same risks that apply to similar investments if held directly by the Portfolio. These risks are described elsewhere in this prospectus. There can be no assurance that the investment objective of the Portfolio or the CRRS Subsidiary will be achieved.

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The CRRS Subsidiary is not registered under the 1940 Act and, unless otherwise noted in this prospectus, is not subject to all the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the CRRS Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the CRRS Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management. PIMCO also serves as the investment adviser for the CRRS Subsidiary.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.74% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.49% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
As discussed in the “Principal Investment Strategies” section, the Portfolio may pursue its investment objective by investing in the CRRS Subsidiary. The CRRS Subsidiary has entered into a separate contract with PIMCO whereby PIMCO provides investment advisory and other services to the CRRS Subsidiary. In consideration of these services, the CRRS Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. PIMCO has contractually agreed to waive the advisory fee and the supervisory and administrative fee it receives from the Portfolio in an amount equal to the management fee and administrative services fee, respectively, paid to PIMCO by the CRRS Subsidiary. This waiver may not be terminated by PIMCO and the waiver will remain in effect for as long as PIMCO’s contract with the CRRS Subsidiary is in place.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not:

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Prospectus

1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO CommodityRealReturn® Strategy
Nicholas J. Johnson
1/15
Managing Director, PIMCO. He joined PIMCO in 2004 and previously managed the portfolio
analyst group. Prior to joining PIMCO, he worked at NASA's Jet Propulsion Laboratory,
developing Mars missions and new methods of autonomous navigation.
PIMCO CommodityRealReturn® Strategy
Steve Rodosky
1/19
Managing Director, PIMCO. Mr. Rodosky joined PIMCO in 2001 and specializes in portfolio
management of treasuries, agencies and futures.
PIMCO CommodityRealReturn® Strategy
Greg E. Sharenow
11/18
Managing Director, PIMCO. Mr. Sharenow joined PIMCO in 2011 and is a portfolio manager
focusing on real assets. Prior to joining PIMCO, he was an energy trader at Hess Energy
Trading, Goldman Sachs and DE Shaw. He was also previously senior energy economist at
Goldman Sachs. He has investment and financial services experience since 2000 and holds
bachelor's degrees in mathematical methods in the social sciences and in economics from
Northwestern University.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”), an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

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conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
A Note on the Portfolio. One of the requirements for favorable tax treatment as a regulated investment company under the Code is that the Portfolio derives at least 90% of its gross income from certain qualifying sources of income. The IRS has issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. As such, the Portfolio’s ability to utilize commodity-linked swaps as part of its investment strategy is limited to a maximum of 10 percent of its gross income.
However, in a subsequent revenue ruling, the IRS provides that income from alternative investment instruments (such as certain commodity index-linked notes) that create commodity exposure may be considered qualifying income under the Code. The IRS has also issued private letter rulings in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued private letter

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rulings in which the IRS specifically concluded that income derived from an investment in a subsidiary will also constitute qualifying income to the Portfolio, even if that subsidiary itself owns commodity-linked swaps. The Portfolio will continue to seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the CRRS Subsidiary.
Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio’s income from an investment in the subsidiary is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the 1940 Act. In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings.There can be no assurance that the IRS will not change its position with respect to some or all of these conclusions or that future legislation will not adversely impact the tax treatment of the Portfolio’s commodity-linked investments. If the IRS were to change or reverse its position, or if future legislation adversely affected the tax treatment of the commodity-linked investments, there would likely be a significant adverse impact on the Portfolio, including the possibility of failing to qualify as a regulated investment company. If the Portfolio did not qualify as a regulated investment company for any taxable year, its taxable income would be subject to tax at the Portfolio level at regular corporate tax rates (without reduction for distributions to shareholders) and to a further tax at the shareholder level when such income is distributed.
Furthermore, the tax treatment of commodity-linked notes, other commodity-linked derivatives, and the Portfolio’s investments in the CRRS Subsidiary may otherwise be adversely affected by future legislation, court decisions, Treasury Regulations and/or guidance issued by the IRS. Such developments could affect the character, timing and/or amount of the Portfolio’s taxable income or any distributions made by the Portfolio or result in the inability of the Portfolio to operate as described in its Prospectus.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various
types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Because the Portfolio may invest a portion of its assets in the CRRS Subsidiary, which may hold some of the investments described in this prospectus, the Portfolio may be indirectly exposed to the risks associated with those investments. With respect to its investments, the CRRS Subsidiary will generally be subject to the same fundamental, non-fundamental and certain other investment restrictions as the Portfolio; however, the CRRS Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. The Portfolio and the CRRS Subsidiary may test for compliance with certain investment restrictions on a consolidated basis, except that with respect to its investments in certain securities that may involve leverage, the CRRS Subsidiary will comply with asset segregation or “earmarking” requirements to the same extent as the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.

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More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum real return. The real return sought by the Portfolio consists of both income earned on the Portfolio's investments and capital appreciation, if any, arising from increases in the market value of the Portfolio's holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors
depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if

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interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC
certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older,

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higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities.

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CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks
of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate

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debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate
securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of

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inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio

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as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
In addition, the Portfolio may invest in equity securities of issuers in commodity-related industries. When investing directly in equity securities, the Portfolio will not be limited to only those equity securities with any particular weighting in the Portfolio's respective benchmark index, if any. Generally, the Portfolio may consider investing directly in equity securities when derivatives on the underlying securities appear to be overvalued.    At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically
tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to

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foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test
determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by

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supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created
significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the

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Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In
addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.

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Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the
costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
A Note on the Portfolio. In light of relevant IRS guidance, as discussed above under “Tax Consequences—A Note on the Portfolio,” the Portfolio will seek to gain exposure to the commodity markets primarily through investments in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices, and through investments in the CRRS Subsidiary (as discussed below). The Portfolio may also invest in commodity-linked notes with principal and/or coupon payments linked to the value of particular commodities or commodity futures contracts, or a subset of commodities and commodities futures contracts. These notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in response to changes in the underlying commodity, commodity futures contract, subset of commodities, subset of commodities futures contracts or commodity index.
These notes expose the Portfolio economically to movements in commodity prices. These notes also are subject to risks, such as credit, market and interest rate risks, that in general affect the values of debt securities. In addition, these notes are often leveraged, increasing the volatility of each note’s market value relative to changes in the underlying commodity, commodity futures contract or commodity index. Therefore, at the maturity of the note, the Portfolio may receive more or less principal than it originally invested. The Portfolio might receive interest payments on the note that are more or less than the stated coupon interest payments.
The Portfolio may also invest in other commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures. The value of a commodity-linked derivative investment generally is based upon the price movements of a physical commodity (such as energy, mineral, or agricultural products), a commodity futures contract, a subset of commodities, a subset of commodities futures contracts or commodity index, or other economic variable based upon changes in the value of commodities or the commodities markets.
Options transactions may be effected on exchanges or in the OTC market. When OTC options are purchased, the Portfolio’s portfolio bears the risk that the counterparty that wrote the option will be unable or unwilling to perform its obligations under the option contract. Options

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may also be illiquid and, in such cases, the Portfolio may have difficulty closing out its position. OTC options also may include options on baskets of specific securities.
Many swap transactions are privately negotiated agreements between the Portfolio and a counterparty to exchange or swap investment cash flows or assets at specified intervals in the future. The obligations may extend beyond one year. There is often no central exchange for swap transactions and therefore they can be less liquid investments than exchange-traded instruments. The Dodd-Frank Act and related regulatory developments require the clearing and exchange-trading of certain standardized OTC derivative instruments that the CFTC and SEC have defined as “swaps.” The CFTC has implemented mandatory exchange-trading and clearing requirements under the Dodd-Frank Act and the CFTC continues to approve contracts for central clearing. Uncleared swaps are subject to margin requirements that are being implemented on a phased-in basis. The investment adviser will continue to monitor these developments, particularly to the extent regulatory changes affect the Portfolio’s ability to enter into swap agreements.
As described below under “Characteristics and Risks of Securities and Investment Techniques—Investments in the Wholly-Owned Subsidiary,” the Portfolio may gain exposure to commodity markets by investing in the CRRS Subsidiary. It is expected that the CRRS Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments.
The IRS issued a revenue ruling that limits the extent to which the Portfolio may invest directly in commodity-linked swaps or certain other commodity-linked derivatives. The CRRS Subsidiary, on the other hand, may invest in these commodity-linked derivatives generally without limitation. See “Tax Consequences—A Note on the Portfolio,” above for further information.
Investments in a Wholly Owned Subsidiary
Investments in the CRRS Subsidiary are expected to provide the Portfolio with exposure to the commodity markets within the limitations of Subchapter M of the Code and recent IRS revenue rulings, as discussed above under “Tax Consequences—A Note on the Portfolio.”
It is expected that the CRRS Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments. Although the Portfolio may enter into these commodity-linked derivative instruments directly, the Portfolio will likely gain exposure to these derivative instruments indirectly by investing in the CRRS Subsidiary. To the extent that PIMCO believes that these commodity-linked derivative instruments are better suited to provide exposure to the commodities market than commodity index-linked notes, the Portfolio’s investment in the CRRS Subsidiary will likely increase. The CRRS Subsidiary will also invest in inflation-indexed securities and/or other Fixed Income Instruments, which are intended to serve as margin or collateral for the CRRS Subsidiary’s derivatives
position, common and preferred securities as well as convertible securities of issuers in commodity-related industries, collateralized debt obligations, event-linked bonds and event-linked swaps. To the extent that the Portfolio invests in the CRRS Subsidiary, it may be subject to the risks associated with those derivative instruments and other securities, which are discussed elsewhere in this prospectus.
While the CRRS Subsidiary may be considered similar to an investment company, it is not registered under the 1940 Act and, unless otherwise noted in the prospectus, is not subject to all of the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the CRRS Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the CRRS Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules

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and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The limitation described in the foregoing sentence shall not apply to the Portfolio’s investment in the CRRS Subsidiary. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO
Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act, and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.

36  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and
reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.

April 30, 2021 | PROSPECTUS  37

PIMCO Variable Insurance Trust

The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV,
process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolio does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

38  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO CommodityRealReturn® Strategy Portfolio (Consolidated)
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$6.41
$0.05
$(0.06)
$(0.01)
$(0.35)
$0.00
$0.00
$(0.35)
12/31/2019
6.02
0.10
0.58
0.68
(0.29)
0.00
0.00
(0.29)
12/31/2018
7.16
0.15
(1.14)
(0.99)
(0.15)
0.00
0.00
(0.15)
12/31/2017
7.87
0.13
(0.01)
0.12
(0.83)
0.00
0.00
(0.83)
12/31/2016
6.91
0.12
0.92
1.04
(0.08)
0.00
0.00
(0.08)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

39  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$6.05
1.35%
$223,298
1.24%
1.38%
0.89%
1.03%
1.02%
250%
6.41
11.43
222,337
2.16
2.27
0.89
1.00
1.54
223
6.02
(14.13)
217,121
1.92
2.07
0.89
1.04
2.19
237
7.16
2.15
263,712
1.40
1.54
0.89
1.03
1.79
157
7.87
15.16
261,084
1.18
1.32
0.89
1.03
1.62
206

April 30, 2021 | PROSPECTUS  40

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1850F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
Real Return Strategy Portfolio
PIMCO CommodityRealReturn® Strategy Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO CommodityRealReturn® Strategy Portfolio

Investment Objective
The Portfolio seeks maximum real return, consistent with prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.74%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.35%
Acquired Fund Fees and Expenses
0.14%
Total Annual Portfolio Operating Expenses
1.48%
Fee Waiver and/or Expense Reimbursement(2)
(0.14%)
Total Annual Portfolio Operating Expenses After Fee Waiver and/or
Expense Reimbursement
1.34%
1
“Other Expenses” include interest expense of 0.35%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 0.99% for Advisor Class shares.
2
PIMCO has contractually agreed to waive the Portfolio’s advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Portfolio I Ltd. (the “CRRS Subsidiary”) to PIMCO. The CRRS Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO’s contract with the CRRS Subsidiary is in place.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$136
$454
$795
$1,756
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 250% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. “Real Return” equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure. The Portfolio invests in commodity-linked derivative instruments, including swap agreements, futures, options on futures, commodity index-linked notes and commodity options, that provide exposure to the investment returns of the commodities markets, without investing directly in physical commodities. Commodities are assets that have tangible properties, such as oil, metals, and agricultural products. The value of commodity-linked derivative instruments may be affected by overall market movements and other factors affecting the value of a particular industry or commodity, such as weather, disease, embargoes, or political and regulatory developments. The Portfolio may also invest in common and preferred securities as well as convertible securities of issuers in commodity-related industries. When determining the target allocation for the strategy, PIMCO may use proprietary quantitative models. The target allocations may include long, short, or no positions in the underlying financial markets and commodities specified in the models. The quantitative models are developed and maintained by PIMCO, and are subject to change over time without notice in PIMCO’s discretion. PIMCO also retains discretion over the final target asset allocation and the implementation of the target asset allocation, which may include positions that are different from target allocations determined by quantitative models.
The Portfolio will generally seek to gain exposure to the commodity markets primarily through investments in swap agreements, futures, and options on futures and through investments in the PIMCO Cayman Commodity Portfolio I Ltd., a wholly-owned subsidiary of the Portfolio organized under the laws of the Cayman Islands (the “CRRS Subsidiary”). The CRRS Subsidiary is advised by PIMCO, and has the same investment objective as the Portfolio. As discussed in greater detail elsewhere in this prospectus, the CRRS Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. In order to comply with certain issuer diversification limits imposed by the Internal Revenue Code, the Portfolio may invest up to 25% of its total assets in the CRRS Subsidiary.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

The derivative instruments in which the Portfolio and the CRRS Subsidiary primarily intend to invest are instruments linked to certain commodity indices. Additionally, the Portfolio or the CRRS Subsidiary may invest in derivative instruments linked to the value of a particular commodity or commodity futures contract, or a subset of commodities or commodity futures contracts. The Portfolio’s or the CRRS Subsidiary’s investments in commodity-linked derivative instruments may specify exposure to commodity futures with different roll dates, reset dates or contract months than those specified by a particular commodity index. As a result, the commodity-linked derivatives component of the Portfolio’s portfolio may deviate from the returns of any particular commodity index. The Portfolio or the CRRS Subsidiary may over-weight or under-weight its exposure to a particular commodity index, or a subset of commodities, such that the Portfolio has greater or lesser exposure to that index than the value of the Portfolio’s net assets, or greater or lesser exposure to a subset of commodities than is represented by a particular commodity index. Such deviations will frequently be the result of temporary market fluctuations, and under normal circumstances the Portfolio will seek to maintain notional exposure to one or more commodity indices within 5% (plus or minus) of the value of the Portfolio’s net assets.
The Portfolio may also invest in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices. These commodity index-linked notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in response to changes in the underlying commodity or related index of investment.
Assets not invested in commodity-linked derivative instruments or the CRRS Subsidiary may be invested in inflation-indexed securities and other Fixed Income Instruments, including derivative Fixed Income Instruments. In addition, the Portfolio may invest its assets in particular sectors of the commodities market.
The average portfolio duration of the fixed income portion of this Portfolio will vary based on PIMCO’s forecast for interest rates and under normal market conditions is not expected to exceed ten years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest up to 30% of its total assets in securities denominated in foreign currencies and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 10% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year
remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The Portfolio may also invest up to 10% of its total assets in preferred securities. The Portfolio may purchase and sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales.
Principal Risks
It is possible to lose money on an investment in the Portfolio. Under certain conditions, generally in a market where the value of both commodity-linked derivative instruments and fixed income securities are declining, the Portfolio may experience substantial losses. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are:
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services

April 30, 2021 | PROSPECTUS  2

PIMCO CommodityRealReturn® Strategy Portfolio

Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Model Risk:the risk that the Portfolio’s investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in the Portfolio
Commodity Risk:the risk that investing in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO, including the use of quantitative models or methods, will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Inflation-Indexed Security Risk:the risk that inflation-indexed debt securities are subject to the effects of changes in market interest rates caused by factors other than inflation (real interest rates). In general, the value of an inflation-indexed security, including TIPS, tends to decrease when real interest rates increase and can increase when real interest rates decrease. Interest payments on inflation-indexed securities are unpredictable and will fluctuate as the principal and interest are

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adjusted for inflation. There can be no assurance that the inflation index used will accurately measure the real rate of inflation in the prices of goods and services. Any increase in the principal amount of an inflation-indexed debt security will be considered taxable ordinary income, even though the Portfolio will not receive the principal until maturity
Tax Risk:the risk that the tax treatment of swap agreements and other derivative instruments, such as commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures, may be affected by future regulatory or legislative changes that could affect whether income from such investments is “qualifying income” under Subchapter M of the Internal Revenue Code, or otherwise affect the character, timing and/or amount of the Portfolio’s taxable income or gains and distributions
Subsidiary Risk:the risk that, by investing in the CRRS Subsidiary, the Portfolio is indirectly exposed to the risks associated with the CRRS Subsidiary’s investments. The CRRS Subsidiary is not registered under the 1940 Act and may not be subject to all the investor protections of the 1940 Act. There is no guarantee that the investment objective of the CRRS Subsidiary will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Commodity Index Total Return is an unmanaged index composed of futures contracts on a number of physical commodities. The index is designed to be a highly liquid and diversified benchmark for commodities as an asset class.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
June 30, 2016
13.66%
Worst Quarter
March 31, 2020
-27.07%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Advisor Class Return
1.23%
2.54%
-5.49%
Bloomberg Commodity Index Total Return (reflects no
deductions for fees, expenses or taxes)
-3.12%
1.03%
-6.50%
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Nicholas J. Johnson, Steve Rodosky and Greg Sharenow. Messrs. Johnson, Rodosky and Sharenow are Managing Directors of PIMCO. Mr. Johnson has managed the Portfolio since January 2015, Mr. Rodosky has managed the Portfolio since January 2019 and Mr. Sharenow has managed the Portfolio since November 2018.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

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PIMCO CommodityRealReturn® Strategy Portfolio

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests. These factors include the possibility that the Portfolio's commodity derivatives positions may have different roll dates, reset dates or contract months than those specified in a particular commodity index.   By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Model Risk
In making investment allocation decisions for the Portfolio PIMCO may utilize quantitative models that may be proprietary or developed by third-parties. These models are used by PIMCO to determine (or assist in determining) the Portfolio’s target asset allocation and to identify potentially attractive relative value and risk hedging strategies. The investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in the Portfolio. There can be no assurance that the models used by PIMCO will remain viable, due to various factors, which may include the quality of the data input into the models and the assumptions underlying such models, which to varying degrees involve the exercise of judgment, as well as the possibility of errors in constructing or using the model.
Models rely on accurate market data inputs. If inaccurate market data is entered into a model, the resulting information will be incorrect. In addition, the models used may be predictive in nature and such models may result in an incorrect assessment of future events. The models evaluate securities or securities markets based on certain assumptions concerning the interplay of market factors. The markets or the prices of individual securities may be affected by factors not foreseen in developing the models. In addition, when relying on a quantitative model and/or data supplied by third parties, PIMCO may have less insight into the construction, coding or testing of the third-party model or data, and PIMCO will be exposed to systems, cyber security and other risks associated with the third party that provides the model or data.
The use of models can be complex and involves financial, economic, econometric and statistical theories, research and modeling; and the results of those processes must then be translated into computer code. Although PIMCO seeks to hire individuals and/or third parties, as applicable, skilled in each of these functions and to provide appropriate levels of oversight, the complexity of the individual tasks, the difficulty of integrating such tasks, and the limited ability to perform “real world” testing of a model’s end product raises the chances that a finished model may contain an error; one or more of such errors could adversely affect the Portfolio’s performance.
Commodity Risk
The Portfolio’s investments in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments. The Portfolio and the CRRS Subsidiary may each concentrate its assets in a particular sector of the commodities market (such as oil, metal or agricultural products). As a result, the Portfolio and the CRRS Subsidiary may be more susceptible to risks associated with those sectors. The prices for commodities in those sectors may fluctuate widely due to factors such as changes in value, supply and demand and governmental regulatory policies.

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Prospectus

Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries

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are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The CRRS Subsidiary will comply with these asset segregation or “earmarking” requirements to the same extent as the Portfolio. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy its obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.

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Prospectus

Management Risk
The Portfolio and the CRRS Subsidiary are subject to management risk because they are actively managed investment portfolios. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis and will, in some cases, rely partially or entirely upon or be informed by one or more quantitative models in making investment decisions for the Portfolio and the CRRS Subsidiary, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio and the CRRS Subsidiary to achieve their investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s and the CRRS Subsidiary’s ability to realize their investment objective. Similarly, there can be no assurance that quantitative models or methods utilized by PIMCO or related data sources will always be available, and the loss of access to any such model(s) or data sources could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Tax Risk
The Portfolio gains exposure to the commodities markets through investments in commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures. The Portfolio may also gain exposure indirectly to commodity markets by investing in the CRRS Subsidiary, which invests primarily in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and/or other Fixed Income Instruments. In order for the Portfolio to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”), the Portfolio must derive at least 90 percent of its gross income each taxable year from certain qualifying sources of income.
As more fully described below under “Tax Consequences-A Note on the Portfolio,” the Internal Revenue Service (the “IRS”) issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. However, the IRS has issued private letter rulings in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued private letter rulings in which the IRS specifically concluded that income derived from an investment in the CRRS Subsidiary will also constitute qualifying income to the Portfolio. Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio’s income from an investment in the subsidiary is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the Investment Company Act of 1940, as amended (the “1940 Act”). In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings.
The Portfolio will seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the CRRS Subsidiary. If the IRS were to determine that income derived from certain commodity-linked notes or from investments in the CRRS Subsidiary does not constitute qualifying income, the Portfolio might be adversely affected and would be required to reduce its exposure to such investments which might result in difficulty in implementing its investment strategies and increased costs and taxes. The use of commodity index-linked notes and investments in the CRRS Subsidiary involve specific risks. See “Characteristics and Risks of Securities and Investment Techniques —Derivatives—A Note on the Portfolio” below for further information regarding commodity index-linked notes, including the risks associated with these instruments. In addition, see “Characteristics and Risks of Securities and Investment Techniques-Investments in the Wholly-Owned Subsidiary” below for further information regarding the CRRS Subsidiary, including the risks associated with investing in the CRRS Subsidiary.
Subsidiary Risk
By investing in the CRRS Subsidiary, the Portfolio is indirectly exposed to the risks associated with the CRRS Subsidiary’s investments. The investments held by the CRRS Subsidiary are generally similar to those that are permitted to be held by the Portfolio and are subject to the same risks that apply to similar investments if held directly by the Portfolio. These risks are described elsewhere in this prospectus. There can be no assurance that the investment objective of the Portfolio or the CRRS Subsidiary will be achieved.

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The CRRS Subsidiary is not registered under the 1940 Act and, unless otherwise noted in this prospectus, is not subject to all the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the CRRS Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the CRRS Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management. PIMCO also serves as the investment adviser for the CRRS Subsidiary.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.74% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.49% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
As discussed in the “Principal Investment Strategies” section, the Portfolio may pursue its investment objective by investing in the CRRS Subsidiary. The CRRS Subsidiary has entered into a separate contract with PIMCO whereby PIMCO provides investment advisory and other services to the CRRS Subsidiary. In consideration of these services, the CRRS Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. PIMCO has contractually agreed to waive the advisory fee and the supervisory and administrative fee it receives from the Portfolio in an amount equal to the management fee and administrative services fee, respectively, paid to PIMCO by the CRRS Subsidiary. This waiver may not be terminated by PIMCO and the waiver will remain in effect for as long as PIMCO’s contract with the CRRS Subsidiary is in place.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not:

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Prospectus

1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO CommodityRealReturn® Strategy
Nicholas J. Johnson
1/15
Managing Director, PIMCO. He joined PIMCO in 2004 and previously managed the portfolio
analyst group. Prior to joining PIMCO, he worked at NASA's Jet Propulsion Laboratory,
developing Mars missions and new methods of autonomous navigation.
PIMCO CommodityRealReturn® Strategy
Steve Rodosky
1/19
Managing Director, PIMCO. Mr. Rodosky joined PIMCO in 2001 and specializes in portfolio
management of treasuries, agencies and futures.
PIMCO CommodityRealReturn® Strategy
Greg E. Sharenow
11/18
Managing Director, PIMCO. Mr. Sharenow joined PIMCO in 2011 and is a portfolio manager
focusing on real assets. Prior to joining PIMCO, he was an energy trader at Hess Energy
Trading, Goldman Sachs and DE Shaw. He was also previously senior energy economist at
Goldman Sachs. He has investment and financial services experience since 2000 and holds
bachelor's degrees in mathematical methods in the social sciences and in economics from
Northwestern University.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

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From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

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circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
A Note on the Portfolio. One of the requirements for favorable tax treatment as a regulated investment company under the Code is that the Portfolio derives at least 90% of its gross income from certain qualifying sources of income. The IRS has issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. As such, the Portfolio’s ability to utilize commodity-linked swaps as part of its investment strategy is limited to a maximum of 10 percent of its gross income.
However, in a subsequent revenue ruling, the IRS provides that income from alternative investment instruments (such as certain commodity index-linked notes) that create commodity exposure may be considered qualifying income under the Code. The IRS has also issued private letter rulings in which the IRS specifically concluded that income from certain

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commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued private letter rulings in which the IRS specifically concluded that income derived from an investment in a subsidiary will also constitute qualifying income to the Portfolio, even if that subsidiary itself owns commodity-linked swaps. The Portfolio will continue to seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the CRRS Subsidiary.
Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio’s income from an investment in the subsidiary is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the 1940 Act. In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings.There can be no assurance that the IRS will not change its position with respect to some or all of these conclusions or that future legislation will not adversely impact the tax treatment of the Portfolio’s commodity-linked investments. If the IRS were to change or reverse its position, or if future legislation adversely affected the tax treatment of the commodity-linked investments, there would likely be a significant adverse impact on the Portfolio, including the possibility of failing to qualify as a regulated investment company. If the Portfolio did not qualify as a regulated investment company for any taxable year, its taxable income would be subject to tax at the Portfolio level at regular corporate tax rates (without reduction for distributions to shareholders) and to a further tax at the shareholder level when such income is distributed.
Furthermore, the tax treatment of commodity-linked notes, other commodity-linked derivatives, and the Portfolio’s investments in the CRRS Subsidiary may otherwise be adversely affected by future legislation, court decisions, Treasury Regulations and/or guidance issued by the IRS. Such developments could affect the character, timing and/or amount of the Portfolio’s taxable income or any distributions made by the Portfolio or result in the inability of the Portfolio to operate as described in its Prospectus.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are
discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Because the Portfolio may invest a portion of its assets in the CRRS Subsidiary, which may hold some of the investments described in this prospectus, the Portfolio may be indirectly exposed to the risks associated with those investments. With respect to its investments, the CRRS Subsidiary will generally be subject to the same fundamental, non-fundamental and certain other investment restrictions as the Portfolio; however, the CRRS Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. The Portfolio and the CRRS Subsidiary may test for compliance with certain investment restrictions on a consolidated basis, except that with respect to its investments in certain securities that may involve leverage, the CRRS Subsidiary will comply with asset segregation or “earmarking” requirements to the same extent as the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.

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More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum real return. The real return sought by the Portfolio consists of both income earned on the Portfolio's investments and capital appreciation, if any, arising from increases in the market value of the Portfolio's holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors
depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if

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interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC
certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older,

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higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities.

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CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks
of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate

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debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate
securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of

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inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio

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as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
In addition, the Portfolio may invest in equity securities of issuers in commodity-related industries. When investing directly in equity securities, the Portfolio will not be limited to only those equity securities with any particular weighting in the Portfolio's respective benchmark index, if any. Generally, the Portfolio may consider investing directly in equity securities when derivatives on the underlying securities appear to be overvalued.    At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically
tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to

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foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test
determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by

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supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created
significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the

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Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In
addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.

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Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the
costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
A Note on the Portfolio. In light of relevant IRS guidance, as discussed above under “Tax Consequences—A Note on the Portfolio,” the Portfolio will seek to gain exposure to the commodity markets primarily through investments in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices, and through investments in the CRRS Subsidiary (as discussed below). The Portfolio may also invest in commodity-linked notes with principal and/or coupon payments linked to the value of particular commodities or commodity futures contracts, or a subset of commodities and commodities futures contracts. These notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in response to changes in the underlying commodity, commodity futures contract, subset of commodities, subset of commodities futures contracts or commodity index.
These notes expose the Portfolio economically to movements in commodity prices. These notes also are subject to risks, such as credit, market and interest rate risks, that in general affect the values of debt securities. In addition, these notes are often leveraged, increasing the volatility of each note’s market value relative to changes in the underlying commodity, commodity futures contract or commodity index. Therefore, at the maturity of the note, the Portfolio may receive more or less principal than it originally invested. The Portfolio might receive interest payments on the note that are more or less than the stated coupon interest payments.
The Portfolio may also invest in other commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures. The value of a commodity-linked derivative investment generally is based upon the price movements of a physical commodity (such as energy, mineral, or agricultural products), a commodity futures contract, a subset of commodities, a subset of commodities futures contracts or commodity index, or other economic variable based upon changes in the value of commodities or the commodities markets.
Options transactions may be effected on exchanges or in the OTC market. When OTC options are purchased, the Portfolio’s portfolio bears the risk that the counterparty that wrote the option will be unable or unwilling to perform its obligations under the option contract. Options

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may also be illiquid and, in such cases, the Portfolio may have difficulty closing out its position. OTC options also may include options on baskets of specific securities.
Many swap transactions are privately negotiated agreements between the Portfolio and a counterparty to exchange or swap investment cash flows or assets at specified intervals in the future. The obligations may extend beyond one year. There is often no central exchange for swap transactions and therefore they can be less liquid investments than exchange-traded instruments. The Dodd-Frank Act and related regulatory developments require the clearing and exchange-trading of certain standardized OTC derivative instruments that the CFTC and SEC have defined as “swaps.” The CFTC has implemented mandatory exchange-trading and clearing requirements under the Dodd-Frank Act and the CFTC continues to approve contracts for central clearing. Uncleared swaps are subject to margin requirements that are being implemented on a phased-in basis. The investment adviser will continue to monitor these developments, particularly to the extent regulatory changes affect the Portfolio’s ability to enter into swap agreements.
As described below under “Characteristics and Risks of Securities and Investment Techniques—Investments in the Wholly-Owned Subsidiary,” the Portfolio may gain exposure to commodity markets by investing in the CRRS Subsidiary. It is expected that the CRRS Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments.
The IRS issued a revenue ruling that limits the extent to which the Portfolio may invest directly in commodity-linked swaps or certain other commodity-linked derivatives. The CRRS Subsidiary, on the other hand, may invest in these commodity-linked derivatives generally without limitation. See “Tax Consequences—A Note on the Portfolio,” above for further information.
Investments in a Wholly Owned Subsidiary
Investments in the CRRS Subsidiary are expected to provide the Portfolio with exposure to the commodity markets within the limitations of Subchapter M of the Code and recent IRS revenue rulings, as discussed above under “Tax Consequences—A Note on the Portfolio.”
It is expected that the CRRS Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments. Although the Portfolio may enter into these commodity-linked derivative instruments directly, the Portfolio will likely gain exposure to these derivative instruments indirectly by investing in the CRRS Subsidiary. To the extent that PIMCO believes that these commodity-linked derivative instruments are better suited to provide exposure to the commodities market than commodity index-linked notes, the Portfolio’s investment in the CRRS Subsidiary will likely increase. The CRRS Subsidiary will also invest in inflation-indexed securities and/or other Fixed Income Instruments, which are intended to serve as margin or collateral for the CRRS Subsidiary’s derivatives
position, common and preferred securities as well as convertible securities of issuers in commodity-related industries, collateralized debt obligations, event-linked bonds and event-linked swaps. To the extent that the Portfolio invests in the CRRS Subsidiary, it may be subject to the risks associated with those derivative instruments and other securities, which are discussed elsewhere in this prospectus.
While the CRRS Subsidiary may be considered similar to an investment company, it is not registered under the 1940 Act and, unless otherwise noted in the prospectus, is not subject to all of the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the CRRS Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the CRRS Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules

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and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The limitation described in the foregoing sentence shall not apply to the Portfolio’s investment in the CRRS Subsidiary. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO
Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act, and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.

36  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and
reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.

April 30, 2021 | PROSPECTUS  37

PIMCO Variable Insurance Trust

The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV,
process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolio does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

38  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO CommodityRealReturn® Strategy Portfolio (Consolidated)
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$6.49
$0.05
$(0.06)
$(0.01)
$(0.35)
$0.00
$0.00
$(0.35)
12/31/2019
6.09
0.09
0.59
0.68
(0.28)
0.00
0.00
(0.28)
12/31/2018
7.24
0.15
(1.16)
(1.01)
(0.14)
0.00
0.00
(0.14)
12/31/2017
7.95
0.12
(0.02)
0.10
(0.81)
0.00
0.00
(0.81)
12/31/2016
6.99
0.14
0.90
1.04
(0.08)
0.00
0.00
(0.08)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

39  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$6.13
1.23%
$111,152
1.34%
1.48%
0.99%
1.13%
0.91%
250%
6.49
11.35
110,525
2.26
2.37
0.99
1.10
1.46
223
6.09
(14.20)
103,329
2.02
2.17
0.99
1.14
2.09
237
7.24
2.05
124,551
1.50
1.64
0.99
1.13
1.69
157
7.95
14.87
127,029
1.28
1.42
0.99
1.13
1.82
206

April 30, 2021 | PROSPECTUS  40

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1838F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
Real Return Strategy Portfolio
PIMCO CommodityRealReturn® Strategy Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO CommodityRealReturn® Strategy Portfolio

Investment Objective
The Portfolio seeks maximum real return, consistent with prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.74%
Other Expenses(1)
0.35%
Acquired Fund Fees and Expenses
0.14%
Total Annual Portfolio Operating Expenses
1.23%
Fee Waiver and/or Expense Reimbursement(2)
(0.14%)
Total Annual Portfolio Operating Expenses After Fee Waiver and/or
Expense Reimbursement
1.09%
1
“Other Expenses” include interest expense of 0.35%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 0.74% for Institutional Class shares.
2
PIMCO has contractually agreed to waive the Portfolio’s advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Portfolio I Ltd. (the “CRRS Subsidiary”) to PIMCO. The CRRS Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO’s contract with the CRRS Subsidiary is in place.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$111
$376
$662
$1,476
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 250% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. “Real Return” equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure. The Portfolio invests in commodity-linked derivative instruments, including swap agreements, futures, options on futures, commodity index-linked notes and commodity options, that provide exposure to the investment returns of the commodities markets, without investing directly in physical commodities. Commodities are assets that have tangible properties, such as oil, metals, and agricultural products. The value of commodity-linked derivative instruments may be affected by overall market movements and other factors affecting the value of a particular industry or commodity, such as weather, disease, embargoes, or political and regulatory developments. The Portfolio may also invest in common and preferred securities as well as convertible securities of issuers in commodity-related industries. When determining the target allocation for the strategy, PIMCO may use proprietary quantitative models. The target allocations may include long, short, or no positions in the underlying financial markets and commodities specified in the models. The quantitative models are developed and maintained by PIMCO, and are subject to change over time without notice in PIMCO’s discretion. PIMCO also retains discretion over the final target asset allocation and the implementation of the target asset allocation, which may include positions that are different from target allocations determined by quantitative models.
The Portfolio will generally seek to gain exposure to the commodity markets primarily through investments in swap agreements, futures, and options on futures and through investments in the PIMCO Cayman Commodity Portfolio I Ltd., a wholly-owned subsidiary of the Portfolio organized under the laws of the Cayman Islands (the “CRRS Subsidiary”). The CRRS Subsidiary is advised by PIMCO, and has the same investment objective as the Portfolio. As discussed in greater detail elsewhere in this prospectus, the CRRS Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. In order to comply with certain issuer diversification limits imposed by the Internal Revenue Code, the Portfolio may invest up to 25% of its total assets in the CRRS Subsidiary.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

The derivative instruments in which the Portfolio and the CRRS Subsidiary primarily intend to invest are instruments linked to certain commodity indices. Additionally, the Portfolio or the CRRS Subsidiary may invest in derivative instruments linked to the value of a particular commodity or commodity futures contract, or a subset of commodities or commodity futures contracts. The Portfolio’s or the CRRS Subsidiary’s investments in commodity-linked derivative instruments may specify exposure to commodity futures with different roll dates, reset dates or contract months than those specified by a particular commodity index. As a result, the commodity-linked derivatives component of the Portfolio’s portfolio may deviate from the returns of any particular commodity index. The Portfolio or the CRRS Subsidiary may over-weight or under-weight its exposure to a particular commodity index, or a subset of commodities, such that the Portfolio has greater or lesser exposure to that index than the value of the Portfolio’s net assets, or greater or lesser exposure to a subset of commodities than is represented by a particular commodity index. Such deviations will frequently be the result of temporary market fluctuations, and under normal circumstances the Portfolio will seek to maintain notional exposure to one or more commodity indices within 5% (plus or minus) of the value of the Portfolio’s net assets.
The Portfolio may also invest in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices. These commodity index-linked notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in response to changes in the underlying commodity or related index of investment.
Assets not invested in commodity-linked derivative instruments or the CRRS Subsidiary may be invested in inflation-indexed securities and other Fixed Income Instruments, including derivative Fixed Income Instruments. In addition, the Portfolio may invest its assets in particular sectors of the commodities market.
The average portfolio duration of the fixed income portion of this Portfolio will vary based on PIMCO’s forecast for interest rates and under normal market conditions is not expected to exceed ten years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest up to 30% of its total assets in securities denominated in foreign currencies and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 10% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year
remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The Portfolio may also invest up to 10% of its total assets in preferred securities. The Portfolio may purchase and sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales.
Principal Risks
It is possible to lose money on an investment in the Portfolio. Under certain conditions, generally in a market where the value of both commodity-linked derivative instruments and fixed income securities are declining, the Portfolio may experience substantial losses. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are:
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services

April 30, 2021 | PROSPECTUS  2

PIMCO CommodityRealReturn® Strategy Portfolio

Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Model Risk:the risk that the Portfolio’s investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in the Portfolio
Commodity Risk:the risk that investing in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO, including the use of quantitative models or methods, will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Inflation-Indexed Security Risk:the risk that inflation-indexed debt securities are subject to the effects of changes in market interest rates caused by factors other than inflation (real interest rates). In general, the value of an inflation-indexed security, including TIPS, tends to decrease when real interest rates increase and can increase when real interest rates decrease. Interest payments on inflation-indexed securities are unpredictable and will fluctuate as the principal and interest are

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Prospectus

adjusted for inflation. There can be no assurance that the inflation index used will accurately measure the real rate of inflation in the prices of goods and services. Any increase in the principal amount of an inflation-indexed debt security will be considered taxable ordinary income, even though the Portfolio will not receive the principal until maturity
Tax Risk:the risk that the tax treatment of swap agreements and other derivative instruments, such as commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures, may be affected by future regulatory or legislative changes that could affect whether income from such investments is “qualifying income” under Subchapter M of the Internal Revenue Code, or otherwise affect the character, timing and/or amount of the Portfolio’s taxable income or gains and distributions
Subsidiary Risk:the risk that, by investing in the CRRS Subsidiary, the Portfolio is indirectly exposed to the risks associated with the CRRS Subsidiary’s investments. The CRRS Subsidiary is not registered under the 1940 Act and may not be subject to all the investor protections of the 1940 Act. There is no guarantee that the investment objective of the CRRS Subsidiary will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Commodity Index Total Return is an unmanaged index composed of futures contracts on a number of physical commodities. The index is designed to be a highly liquid and diversified benchmark for commodities as an asset class.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class
Best Quarter
June 30, 2016
13.78%
Worst Quarter
March 31, 2020
-26.98%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Institutional Class Return
1.50%
2.82%
-5.59%
4/30/2012
Bloomberg Commodity Index Total
Return (reflects no deductions for fees,
expenses or taxes)
-3.12%
1.03%
-5.96%
 
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Nicholas J. Johnson, Steve Rodosky and Greg Sharenow. Messrs. Johnson, Rodosky and Sharenow are Managing Directors of PIMCO. Mr. Johnson has managed the Portfolio since January 2015, Mr. Rodosky has managed the Portfolio since January 2019 and Mr. Sharenow has managed the Portfolio since November 2018.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

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PIMCO CommodityRealReturn® Strategy Portfolio

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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Prospectus

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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Prospectus

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests. These factors include the possibility that the Portfolio's commodity derivatives positions may have different roll dates, reset dates or contract months than those specified in a particular commodity index.   By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Model Risk
In making investment allocation decisions for the Portfolio PIMCO may utilize quantitative models that may be proprietary or developed by third-parties. These models are used by PIMCO to determine (or assist in determining) the Portfolio’s target asset allocation and to identify potentially attractive relative value and risk hedging strategies. The investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in the Portfolio. There can be no assurance that the models used by PIMCO will remain viable, due to various factors, which may include the quality of the data input into the models and the assumptions underlying such models, which to varying degrees involve the exercise of judgment, as well as the possibility of errors in constructing or using the model.
Models rely on accurate market data inputs. If inaccurate market data is entered into a model, the resulting information will be incorrect. In addition, the models used may be predictive in nature and such models may result in an incorrect assessment of future events. The models evaluate securities or securities markets based on certain assumptions concerning the interplay of market factors. The markets or the prices of individual securities may be affected by factors not foreseen in developing the models. In addition, when relying on a quantitative model and/or data supplied by third parties, PIMCO may have less insight into the construction, coding or testing of the third-party model or data, and PIMCO will be exposed to systems, cyber security and other risks associated with the third party that provides the model or data.
The use of models can be complex and involves financial, economic, econometric and statistical theories, research and modeling; and the results of those processes must then be translated into computer code. Although PIMCO seeks to hire individuals and/or third parties, as applicable, skilled in each of these functions and to provide appropriate levels of oversight, the complexity of the individual tasks, the difficulty of integrating such tasks, and the limited ability to perform “real world” testing of a model’s end product raises the chances that a finished model may contain an error; one or more of such errors could adversely affect the Portfolio’s performance.
Commodity Risk
The Portfolio’s investments in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments. The Portfolio and the CRRS Subsidiary may each concentrate its assets in a particular sector of the commodities market (such as oil, metal or agricultural products). As a result, the Portfolio and the CRRS Subsidiary may be more susceptible to risks associated with those sectors. The prices for commodities in those sectors may fluctuate widely due to factors such as changes in value, supply and demand and governmental regulatory policies.

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Prospectus

Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries

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are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The CRRS Subsidiary will comply with these asset segregation or “earmarking” requirements to the same extent as the Portfolio. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy its obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.

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Prospectus

Management Risk
The Portfolio and the CRRS Subsidiary are subject to management risk because they are actively managed investment portfolios. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis and will, in some cases, rely partially or entirely upon or be informed by one or more quantitative models in making investment decisions for the Portfolio and the CRRS Subsidiary, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio and the CRRS Subsidiary to achieve their investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s and the CRRS Subsidiary’s ability to realize their investment objective. Similarly, there can be no assurance that quantitative models or methods utilized by PIMCO or related data sources will always be available, and the loss of access to any such model(s) or data sources could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Tax Risk
The Portfolio gains exposure to the commodities markets through investments in commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures. The Portfolio may also gain exposure indirectly to commodity markets by investing in the CRRS Subsidiary, which invests primarily in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and/or other Fixed Income Instruments. In order for the Portfolio to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”), the Portfolio must derive at least 90 percent of its gross income each taxable year from certain qualifying sources of income.
As more fully described below under “Tax Consequences-A Note on the Portfolio,” the Internal Revenue Service (the “IRS”) issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. However, the IRS has issued private letter rulings in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued private letter rulings in which the IRS specifically concluded that income derived from an investment in the CRRS Subsidiary will also constitute qualifying income to the Portfolio. Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio’s income from an investment in the subsidiary is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the Investment Company Act of 1940, as amended (the “1940 Act”). In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings.
The Portfolio will seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the CRRS Subsidiary. If the IRS were to determine that income derived from certain commodity-linked notes or from investments in the CRRS Subsidiary does not constitute qualifying income, the Portfolio might be adversely affected and would be required to reduce its exposure to such investments which might result in difficulty in implementing its investment strategies and increased costs and taxes. The use of commodity index-linked notes and investments in the CRRS Subsidiary involve specific risks. See “Characteristics and Risks of Securities and Investment Techniques —Derivatives—A Note on the Portfolio” below for further information regarding commodity index-linked notes, including the risks associated with these instruments. In addition, see “Characteristics and Risks of Securities and Investment Techniques-Investments in the Wholly-Owned Subsidiary” below for further information regarding the CRRS Subsidiary, including the risks associated with investing in the CRRS Subsidiary.
Subsidiary Risk
By investing in the CRRS Subsidiary, the Portfolio is indirectly exposed to the risks associated with the CRRS Subsidiary’s investments. The investments held by the CRRS Subsidiary are generally similar to those that are permitted to be held by the Portfolio and are subject to the same risks that apply to similar investments if held directly by the Portfolio. These risks are described elsewhere in this prospectus. There can be no assurance that the investment objective of the Portfolio or the CRRS Subsidiary will be achieved.

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The CRRS Subsidiary is not registered under the 1940 Act and, unless otherwise noted in this prospectus, is not subject to all the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the CRRS Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the CRRS Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management. PIMCO also serves as the investment adviser for the CRRS Subsidiary.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.74% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.49% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
As discussed in the “Principal Investment Strategies” section, the Portfolio may pursue its investment objective by investing in the CRRS Subsidiary. The CRRS Subsidiary has entered into a separate contract with PIMCO whereby PIMCO provides investment advisory and other services to the CRRS Subsidiary. In consideration of these services, the CRRS Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. PIMCO has contractually agreed to waive the advisory fee and the supervisory and administrative fee it receives from the Portfolio in an amount equal to the management fee and administrative services fee, respectively, paid to PIMCO by the CRRS Subsidiary. This waiver may not be terminated by PIMCO and the waiver will remain in effect for as long as PIMCO’s contract with the CRRS Subsidiary is in place.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not:

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Prospectus

1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO CommodityRealReturn® Strategy
Nicholas J. Johnson
1/15
Managing Director, PIMCO. He joined PIMCO in 2004 and previously managed the portfolio
analyst group. Prior to joining PIMCO, he worked at NASA's Jet Propulsion Laboratory,
developing Mars missions and new methods of autonomous navigation.
PIMCO CommodityRealReturn® Strategy
Steve Rodosky
1/19
Managing Director, PIMCO. Mr. Rodosky joined PIMCO in 2001 and specializes in portfolio
management of treasuries, agencies and futures.
PIMCO CommodityRealReturn® Strategy
Greg E. Sharenow
11/18
Managing Director, PIMCO. Mr. Sharenow joined PIMCO in 2011 and is a portfolio manager
focusing on real assets. Prior to joining PIMCO, he was an energy trader at Hess Energy
Trading, Goldman Sachs and DE Shaw. He was also previously senior energy economist at
Goldman Sachs. He has investment and financial services experience since 2000 and holds
bachelor's degrees in mathematical methods in the social sciences and in economics from
Northwestern University.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

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From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

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investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
A Note on the Portfolio. One of the requirements for favorable tax treatment as a regulated investment company under the Code is that the Portfolio derives at least 90% of its gross income from certain qualifying sources of income. The IRS has issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. As such, the Portfolio’s ability to utilize commodity-linked swaps as part of its investment strategy is limited to a maximum of 10 percent of its gross income.
However, in a subsequent revenue ruling, the IRS provides that income from alternative investment instruments (such as certain commodity index-linked notes) that create commodity exposure may be considered qualifying income under the Code. The IRS has also issued private letter rulings in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued private letter rulings in which the IRS specifically concluded that income derived from an investment in a subsidiary will also constitute qualifying income to the Portfolio, even if that subsidiary itself owns commodity-linked swaps. The Portfolio will continue to seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the CRRS Subsidiary.
Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio’s income from an investment in the subsidiary is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the 1940 Act. In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings.There can be no assurance that the IRS will not change its position with respect to some or all of these conclusions or that future legislation will not adversely impact the tax treatment of the

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Portfolio’s commodity-linked investments. If the IRS were to change or reverse its position, or if future legislation adversely affected the tax treatment of the commodity-linked investments, there would likely be a significant adverse impact on the Portfolio, including the possibility of failing to qualify as a regulated investment company. If the Portfolio did not qualify as a regulated investment company for any taxable year, its taxable income would be subject to tax at the Portfolio level at regular corporate tax rates (without reduction for distributions to shareholders) and to a further tax at the shareholder level when such income is distributed.
Furthermore, the tax treatment of commodity-linked notes, other commodity-linked derivatives, and the Portfolio’s investments in the CRRS Subsidiary may otherwise be adversely affected by future legislation, court decisions, Treasury Regulations and/or guidance issued by the IRS. Such developments could affect the character, timing and/or amount of the Portfolio’s taxable income or any distributions made by the Portfolio or result in the inability of the Portfolio to operate as described in its Prospectus.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Because the Portfolio may invest a portion of its assets in the CRRS Subsidiary, which may hold some of the investments described in this prospectus, the Portfolio may be indirectly exposed to the risks associated with those investments. With respect to its investments, the CRRS Subsidiary will generally be subject to the same fundamental, non-fundamental and certain other investment restrictions as the Portfolio; however, the CRRS Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. The Portfolio and the CRRS Subsidiary may test for compliance with certain investment restrictions
on a consolidated basis, except that with respect to its investments in certain securities that may involve leverage, the CRRS Subsidiary will comply with asset segregation or “earmarking” requirements to the same extent as the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other

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shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum real return. The real return sought by the Portfolio consists of both income earned on the Portfolio's investments and capital appreciation, if any, arising from increases in the market value of the Portfolio's holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of

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U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain
municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.

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The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued

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mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to
purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to

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real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate
inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain

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unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
In addition, the Portfolio may invest in equity securities of issuers in commodity-related industries. When investing directly in equity securities, the Portfolio will not be limited to only those equity securities with any particular weighting in the Portfolio's respective benchmark index, if any. Generally, the Portfolio may consider investing directly in equity securities when derivatives on the underlying securities appear to be overvalued.    At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of

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bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor
to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to

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developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of
securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will

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deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur
additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps

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and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the
Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the

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value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
A Note on the Portfolio. In light of relevant IRS guidance, as discussed above under “Tax Consequences—A Note on the Portfolio,” the Portfolio will seek to gain exposure to the commodity markets primarily through investments in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices, and through investments in the CRRS Subsidiary (as discussed below). The Portfolio may
also invest in commodity-linked notes with principal and/or coupon payments linked to the value of particular commodities or commodity futures contracts, or a subset of commodities and commodities futures contracts. These notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in response to changes in the underlying commodity, commodity futures contract, subset of commodities, subset of commodities futures contracts or commodity index.
These notes expose the Portfolio economically to movements in commodity prices. These notes also are subject to risks, such as credit, market and interest rate risks, that in general affect the values of debt securities. In addition, these notes are often leveraged, increasing the volatility of each note’s market value relative to changes in the underlying commodity, commodity futures contract or commodity index. Therefore, at the maturity of the note, the Portfolio may receive more or less principal than it originally invested. The Portfolio might receive interest payments on the note that are more or less than the stated coupon interest payments.
The Portfolio may also invest in other commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures. The value of a commodity-linked derivative investment generally is based upon the price movements of a physical commodity (such as energy, mineral, or agricultural products), a commodity futures contract, a subset of commodities, a subset of commodities futures contracts or commodity index, or other economic variable based upon changes in the value of commodities or the commodities markets.
Options transactions may be effected on exchanges or in the OTC market. When OTC options are purchased, the Portfolio’s portfolio bears the risk that the counterparty that wrote the option will be unable or unwilling to perform its obligations under the option contract. Options may also be illiquid and, in such cases, the Portfolio may have difficulty closing out its position. OTC options also may include options on baskets of specific securities.
Many swap transactions are privately negotiated agreements between the Portfolio and a counterparty to exchange or swap investment cash flows or assets at specified intervals in the future. The obligations may extend beyond one year. There is often no central exchange for swap transactions and therefore they can be less liquid investments than exchange-traded instruments. The Dodd-Frank Act and related regulatory developments require the clearing and exchange-trading of certain standardized OTC derivative instruments that the CFTC and SEC have defined as “swaps.” The CFTC has implemented mandatory exchange-trading and clearing requirements under the Dodd-Frank Act and the CFTC continues to approve contracts for central clearing. Uncleared swaps are subject to margin requirements that are being implemented on a phased-in basis. The investment adviser will continue to monitor these developments, particularly to the extent regulatory changes affect the Portfolio’s ability to enter into swap agreements.

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As described below under “Characteristics and Risks of Securities and Investment Techniques—Investments in the Wholly-Owned Subsidiary,” the Portfolio may gain exposure to commodity markets by investing in the CRRS Subsidiary. It is expected that the CRRS Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments.
The IRS issued a revenue ruling that limits the extent to which the Portfolio may invest directly in commodity-linked swaps or certain other commodity-linked derivatives. The CRRS Subsidiary, on the other hand, may invest in these commodity-linked derivatives generally without limitation. See “Tax Consequences—A Note on the Portfolio,” above for further information.
Investments in a Wholly Owned Subsidiary
Investments in the CRRS Subsidiary are expected to provide the Portfolio with exposure to the commodity markets within the limitations of Subchapter M of the Code and recent IRS revenue rulings, as discussed above under “Tax Consequences—A Note on the Portfolio.”
It is expected that the CRRS Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments. Although the Portfolio may enter into these commodity-linked derivative instruments directly, the Portfolio will likely gain exposure to these derivative instruments indirectly by investing in the CRRS Subsidiary. To the extent that PIMCO believes that these commodity-linked derivative instruments are better suited to provide exposure to the commodities market than commodity index-linked notes, the Portfolio’s investment in the CRRS Subsidiary will likely increase. The CRRS Subsidiary will also invest in inflation-indexed securities and/or other Fixed Income Instruments, which are intended to serve as margin or collateral for the CRRS Subsidiary’s derivatives position, common and preferred securities as well as convertible securities of issuers in commodity-related industries, collateralized debt obligations, event-linked bonds and event-linked swaps. To the extent that the Portfolio invests in the CRRS Subsidiary, it may be subject to the risks associated with those derivative instruments and other securities, which are discussed elsewhere in this prospectus.
While the CRRS Subsidiary may be considered similar to an investment company, it is not registered under the 1940 Act and, unless otherwise noted in the prospectus, is not subject to all of the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the CRRS Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the CRRS Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will

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decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The limitation described in the foregoing sentence shall not apply to the Portfolio’s investment in the CRRS Subsidiary. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act, and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain

36  Prospectus | PIMCO Variable Insurance Trust

Prospectus

commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.

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PIMCO Variable Insurance Trust

Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolio does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service
providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

38  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO CommodityRealReturn® Strategy Portfolio (Consolidated)
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$6.39
$0.07
$(0.07)
$0.00
$(0.36)
$0.00
$0.00
$(0.36)
12/31/2019
6.00
0.10
0.59
0.69
(0.30)
0.00
0.00
(0.30)
12/31/2018
7.14
0.16
(1.14)
(0.98)
(0.16)
0.00
0.00
(0.16)
12/31/2017
7.84
0.14
(0.01)
0.13
(0.83)
0.00
0.00
(0.83)
12/31/2016
6.89
0.13
0.91
1.04
(0.09)
0.00
0.00
(0.09)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

39  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$6.03
1.50%
$2,976
1.09%
1.23%
0.74%
0.88%
1.28%
250%
6.39
11.63
2,895
2.01
2.12
0.74
0.85
1.61
223
6.00
(14.05)
3,000
1.77
1.92
0.74
0.89
2.32
237
7.14
2.40
2,883
1.25
1.39
0.74
0.88
1.92
157
7.84
15.22
2,813
1.03
1.17
0.74
0.88
1.82
206

April 30, 2021 | PROSPECTUS  40

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2050F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: M
Real Return Strategy Portfolio
PIMCO CommodityRealReturn® Strategy Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO CommodityRealReturn® Strategy Portfolio

Investment Objective
The Portfolio seeks maximum real return, consistent with prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Class M shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Class M
Management Fees
0.74%
Distribution and/or Service (12b-1) Fees
0.45%
Other Expenses(1)
0.35%
Acquired Fund Fees and Expenses
0.14%
Total Annual Portfolio Operating Expenses
1.68%
Fee Waiver and/or Expense Reimbursement(2)
(0.14%)
Total Annual Portfolio Operating Expenses After Fee Waiver and/or
Expense Reimbursement
1.54%
1
“Other Expenses” include interest expense of 0.35%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 1.19% for Class M shares.
2
PIMCO has contractually agreed to waive the Portfolio’s advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Portfolio I Ltd. (the “CRRS Subsidiary”) to PIMCO. The CRRS Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO’s contract with the CRRS Subsidiary is in place.
Example.The Example is intended to help you compare the cost of investing in Class M shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Class M
$157
$516
$899
$1,975
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 250% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. “Real Return” equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure. The Portfolio invests in commodity-linked derivative instruments, including swap agreements, futures, options on futures, commodity index-linked notes and commodity options, that provide exposure to the investment returns of the commodities markets, without investing directly in physical commodities. Commodities are assets that have tangible properties, such as oil, metals, and agricultural products. The value of commodity-linked derivative instruments may be affected by overall market movements and other factors affecting the value of a particular industry or commodity, such as weather, disease, embargoes, or political and regulatory developments. The Portfolio may also invest in common and preferred securities as well as convertible securities of issuers in commodity-related industries. When determining the target allocation for the strategy, PIMCO may use proprietary quantitative models. The target allocations may include long, short, or no positions in the underlying financial markets and commodities specified in the models. The quantitative models are developed and maintained by PIMCO, and are subject to change over time without notice in PIMCO’s discretion. PIMCO also retains discretion over the final target asset allocation and the implementation of the target asset allocation, which may include positions that are different from target allocations determined by quantitative models.
The Portfolio will generally seek to gain exposure to the commodity markets primarily through investments in swap agreements, futures, and options on futures and through investments in the PIMCO Cayman Commodity Portfolio I Ltd., a wholly-owned subsidiary of the Portfolio organized under the laws of the Cayman Islands (the “CRRS Subsidiary”). The CRRS Subsidiary is advised by PIMCO, and has the same investment objective as the Portfolio. As discussed in greater detail elsewhere in this prospectus, the CRRS Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. In order to comply with certain issuer diversification limits imposed by the Internal Revenue Code, the Portfolio may invest up to 25% of its total assets in the CRRS Subsidiary.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

The derivative instruments in which the Portfolio and the CRRS Subsidiary primarily intend to invest are instruments linked to certain commodity indices. Additionally, the Portfolio or the CRRS Subsidiary may invest in derivative instruments linked to the value of a particular commodity or commodity futures contract, or a subset of commodities or commodity futures contracts. The Portfolio’s or the CRRS Subsidiary’s investments in commodity-linked derivative instruments may specify exposure to commodity futures with different roll dates, reset dates or contract months than those specified by a particular commodity index. As a result, the commodity-linked derivatives component of the Portfolio’s portfolio may deviate from the returns of any particular commodity index. The Portfolio or the CRRS Subsidiary may over-weight or under-weight its exposure to a particular commodity index, or a subset of commodities, such that the Portfolio has greater or lesser exposure to that index than the value of the Portfolio’s net assets, or greater or lesser exposure to a subset of commodities than is represented by a particular commodity index. Such deviations will frequently be the result of temporary market fluctuations, and under normal circumstances the Portfolio will seek to maintain notional exposure to one or more commodity indices within 5% (plus or minus) of the value of the Portfolio’s net assets.
The Portfolio may also invest in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices. These commodity index-linked notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in response to changes in the underlying commodity or related index of investment.
Assets not invested in commodity-linked derivative instruments or the CRRS Subsidiary may be invested in inflation-indexed securities and other Fixed Income Instruments, including derivative Fixed Income Instruments. In addition, the Portfolio may invest its assets in particular sectors of the commodities market.
The average portfolio duration of the fixed income portion of this Portfolio will vary based on PIMCO’s forecast for interest rates and under normal market conditions is not expected to exceed ten years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest up to 30% of its total assets in securities denominated in foreign currencies and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 10% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year
remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The Portfolio may also invest up to 10% of its total assets in preferred securities. The Portfolio may purchase and sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales.
Principal Risks
It is possible to lose money on an investment in the Portfolio. Under certain conditions, generally in a market where the value of both commodity-linked derivative instruments and fixed income securities are declining, the Portfolio may experience substantial losses. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are:
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services

April 30, 2021 | PROSPECTUS  2

PIMCO CommodityRealReturn® Strategy Portfolio

Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Model Risk:the risk that the Portfolio’s investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in the Portfolio
Commodity Risk:the risk that investing in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO, including the use of quantitative models or methods, will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Inflation-Indexed Security Risk:the risk that inflation-indexed debt securities are subject to the effects of changes in market interest rates caused by factors other than inflation (real interest rates). In general, the value of an inflation-indexed security, including TIPS, tends to decrease when real interest rates increase and can increase when real interest rates decrease. Interest payments on inflation-indexed securities are unpredictable and will fluctuate as the principal and interest are

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adjusted for inflation. There can be no assurance that the inflation index used will accurately measure the real rate of inflation in the prices of goods and services. Any increase in the principal amount of an inflation-indexed debt security will be considered taxable ordinary income, even though the Portfolio will not receive the principal until maturity
Tax Risk:the risk that the tax treatment of swap agreements and other derivative instruments, such as commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures, may be affected by future regulatory or legislative changes that could affect whether income from such investments is “qualifying income” under Subchapter M of the Internal Revenue Code, or otherwise affect the character, timing and/or amount of the Portfolio’s taxable income or gains and distributions
Subsidiary Risk:the risk that, by investing in the CRRS Subsidiary, the Portfolio is indirectly exposed to the risks associated with the CRRS Subsidiary’s investments. The CRRS Subsidiary is not registered under the 1940 Act and may not be subject to all the investor protections of the 1940 Act. There is no guarantee that the investment objective of the CRRS Subsidiary will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart shows performance of the Portfolio’s Class M shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Commodity Index Total Return is an unmanaged index composed of futures contracts on a number of physical commodities. The index is designed to be a highly liquid and diversified benchmark for commodities as an asset class.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Class M
Best Quarter
June 30, 2016
13.70%
Worst Quarter
March 31, 2020
-27.14%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Class M Return
1.08%
2.35%
-5.11%
11/10/2014
Bloomberg Commodity Index Total
Return (reflects no deductions for fees,
expenses or taxes)
-3.12%
1.03%
-5.43%
 
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Nicholas J. Johnson, Steve Rodosky and Greg Sharenow. Messrs. Johnson, Rodosky and Sharenow are Managing Directors of PIMCO. Mr. Johnson has managed the Portfolio since January 2015, Mr. Rodosky has managed the Portfolio since January 2019 and Mr. Sharenow has managed the Portfolio since November 2018.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

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PIMCO CommodityRealReturn® Strategy Portfolio

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests. These factors include the possibility that the Portfolio's commodity derivatives positions may have different roll dates, reset dates or contract months than those specified in a particular commodity index.   By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Model Risk
In making investment allocation decisions for the Portfolio PIMCO may utilize quantitative models that may be proprietary or developed by third-parties. These models are used by PIMCO to determine (or assist in determining) the Portfolio’s target asset allocation and to identify potentially attractive relative value and risk hedging strategies. The investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in the Portfolio. There can be no assurance that the models used by PIMCO will remain viable, due to various factors, which may include the quality of the data input into the models and the assumptions underlying such models, which to varying degrees involve the exercise of judgment, as well as the possibility of errors in constructing or using the model.
Models rely on accurate market data inputs. If inaccurate market data is entered into a model, the resulting information will be incorrect. In addition, the models used may be predictive in nature and such models may result in an incorrect assessment of future events. The models evaluate securities or securities markets based on certain assumptions concerning the interplay of market factors. The markets or the prices of individual securities may be affected by factors not foreseen in developing the models. In addition, when relying on a quantitative model and/or data supplied by third parties, PIMCO may have less insight into the construction, coding or testing of the third-party model or data, and PIMCO will be exposed to systems, cyber security and other risks associated with the third party that provides the model or data.
The use of models can be complex and involves financial, economic, econometric and statistical theories, research and modeling; and the results of those processes must then be translated into computer code. Although PIMCO seeks to hire individuals and/or third parties, as applicable, skilled in each of these functions and to provide appropriate levels of oversight, the complexity of the individual tasks, the difficulty of integrating such tasks, and the limited ability to perform “real world” testing of a model’s end product raises the chances that a finished model may contain an error; one or more of such errors could adversely affect the Portfolio’s performance.
Commodity Risk
The Portfolio’s investments in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments. The Portfolio and the CRRS Subsidiary may each concentrate its assets in a particular sector of the commodities market (such as oil, metal or agricultural products). As a result, the Portfolio and the CRRS Subsidiary may be more susceptible to risks associated with those sectors. The prices for commodities in those sectors may fluctuate widely due to factors such as changes in value, supply and demand and governmental regulatory policies.

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Prospectus

Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries

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are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The CRRS Subsidiary will comply with these asset segregation or “earmarking” requirements to the same extent as the Portfolio. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy its obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.

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Prospectus

Management Risk
The Portfolio and the CRRS Subsidiary are subject to management risk because they are actively managed investment portfolios. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis and will, in some cases, rely partially or entirely upon or be informed by one or more quantitative models in making investment decisions for the Portfolio and the CRRS Subsidiary, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio and the CRRS Subsidiary to achieve their investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s and the CRRS Subsidiary’s ability to realize their investment objective. Similarly, there can be no assurance that quantitative models or methods utilized by PIMCO or related data sources will always be available, and the loss of access to any such model(s) or data sources could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Tax Risk
The Portfolio gains exposure to the commodities markets through investments in commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures. The Portfolio may also gain exposure indirectly to commodity markets by investing in the CRRS Subsidiary, which invests primarily in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and/or other Fixed Income Instruments. In order for the Portfolio to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”), the Portfolio must derive at least 90 percent of its gross income each taxable year from certain qualifying sources of income.
As more fully described below under “Tax Consequences-A Note on the Portfolio,” the Internal Revenue Service (the “IRS”) issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. However, the IRS has issued private letter rulings in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued private letter rulings in which the IRS specifically concluded that income derived from an investment in the CRRS Subsidiary will also constitute qualifying income to the Portfolio. Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio’s income from an investment in the subsidiary is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the Investment Company Act of 1940, as amended (the “1940 Act”). In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings.
The Portfolio will seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the CRRS Subsidiary. If the IRS were to determine that income derived from certain commodity-linked notes or from investments in the CRRS Subsidiary does not constitute qualifying income, the Portfolio might be adversely affected and would be required to reduce its exposure to such investments which might result in difficulty in implementing its investment strategies and increased costs and taxes. The use of commodity index-linked notes and investments in the CRRS Subsidiary involve specific risks. See “Characteristics and Risks of Securities and Investment Techniques —Derivatives—A Note on the Portfolio” below for further information regarding commodity index-linked notes, including the risks associated with these instruments. In addition, see “Characteristics and Risks of Securities and Investment Techniques-Investments in the Wholly-Owned Subsidiary” below for further information regarding the CRRS Subsidiary, including the risks associated with investing in the CRRS Subsidiary.
Subsidiary Risk
By investing in the CRRS Subsidiary, the Portfolio is indirectly exposed to the risks associated with the CRRS Subsidiary’s investments. The investments held by the CRRS Subsidiary are generally similar to those that are permitted to be held by the Portfolio and are subject to the same risks that apply to similar investments if held directly by the Portfolio. These risks are described elsewhere in this prospectus. There can be no assurance that the investment objective of the Portfolio or the CRRS Subsidiary will be achieved.

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The CRRS Subsidiary is not registered under the 1940 Act and, unless otherwise noted in this prospectus, is not subject to all the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the CRRS Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the CRRS Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management. PIMCO also serves as the investment adviser for the CRRS Subsidiary.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.74% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.49% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
As discussed in the “Principal Investment Strategies” section, the Portfolio may pursue its investment objective by investing in the CRRS Subsidiary. The CRRS Subsidiary has entered into a separate contract with PIMCO whereby PIMCO provides investment advisory and other services to the CRRS Subsidiary. In consideration of these services, the CRRS Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. PIMCO has contractually agreed to waive the advisory fee and the supervisory and administrative fee it receives from the Portfolio in an amount equal to the management fee and administrative services fee, respectively, paid to PIMCO by the CRRS Subsidiary. This waiver may not be terminated by PIMCO and the waiver will remain in effect for as long as PIMCO’s contract with the CRRS Subsidiary is in place.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Class M shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Class M shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Class M shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not:

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Prospectus

1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO CommodityRealReturn® Strategy
Nicholas J. Johnson
1/15
Managing Director, PIMCO. He joined PIMCO in 2004 and previously managed the portfolio
analyst group. Prior to joining PIMCO, he worked at NASA's Jet Propulsion Laboratory,
developing Mars missions and new methods of autonomous navigation.
PIMCO CommodityRealReturn® Strategy
Steve Rodosky
1/19
Managing Director, PIMCO. Mr. Rodosky joined PIMCO in 2001 and specializes in portfolio
management of treasuries, agencies and futures.
PIMCO CommodityRealReturn® Strategy
Greg E. Sharenow
11/18
Managing Director, PIMCO. Mr. Sharenow joined PIMCO in 2011 and is a portfolio manager
focusing on real assets. Prior to joining PIMCO, he was an energy trader at Hess Energy
Trading, Goldman Sachs and DE Shaw. He was also previously senior energy economist at
Goldman Sachs. He has investment and financial services experience since 2000 and holds
bachelor's degrees in mathematical methods in the social sciences and in economics from
Northwestern University.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Class M Shares
The Trust offers investors Class M shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Class M shares.
Distribution and/or Service (12b-1) Fees – Class M Shares. The Trust has adopted a Distribution and Servicing Plan for the Class M shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Class M shares and/or certain shareholder services to Class M shareholders at an annual rate of up to 0.25% of the Portfolio’s average daily net assets attributable to its Class M shares (the “Distribution Fee”).
The Distribution and Servicing Plan also permits the Portfolio to compensate the Distributor for providing or procuring administrative, recordkeeping, and other investor services at an annual rate with respect to the Portfolio not to exceed 0.20% of the average daily net assets of the Portfolio attributable to Class M shares (the “Servicing Fee”).
Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio’s Class M assets on an ongoing basis, over time they will increase the cost of an investment in Class M shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements. Class M shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Class M shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective
owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to

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insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase

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of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

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circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.

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Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
A Note on the Portfolio. One of the requirements for favorable tax treatment as a regulated investment company under the Code is that the Portfolio derives at least 90% of its gross income from certain qualifying sources of income. The IRS has issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. As such, the Portfolio’s ability to utilize commodity-linked swaps as part of its investment strategy is limited to a maximum of 10 percent of its gross income.
However, in a subsequent revenue ruling, the IRS provides that income from alternative investment instruments (such as certain commodity index-linked notes) that create commodity exposure may be considered qualifying income under the Code. The IRS has also issued private letter rulings in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued private letter rulings in which the IRS specifically concluded that income derived from an investment in a subsidiary will also constitute qualifying income to the Portfolio, even if that subsidiary itself owns commodity-linked swaps. The Portfolio will continue to seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the CRRS Subsidiary.
Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio’s income from an investment in the subsidiary is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the 1940 Act. In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings.There can be no assurance that the IRS will not change its position with respect to some or all of these conclusions or that future legislation will not adversely impact the tax treatment of the Portfolio’s commodity-linked investments. If the IRS were to change or reverse its position, or if future legislation adversely affected the tax treatment of the commodity-linked investments, there would likely be a significant adverse impact on the Portfolio, including the possibility of failing to qualify as a regulated investment company. If the Portfolio did not qualify as a regulated investment company for any taxable year, its taxable income would be subject to tax at the Portfolio level at regular corporate tax rates (without reduction for distributions to shareholders) and to a further tax at the shareholder level when such income is distributed.
Furthermore, the tax treatment of commodity-linked notes, other commodity-linked derivatives, and the Portfolio’s investments in the CRRS Subsidiary may otherwise be adversely affected by future legislation, court decisions, Treasury Regulations and/or guidance issued by the IRS. Such developments could affect the character, timing and/or
amount of the Portfolio’s taxable income or any distributions made by the Portfolio or result in the inability of the Portfolio to operate as described in its Prospectus.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Because the Portfolio may invest a portion of its assets in the CRRS Subsidiary, which may hold some of the investments described in this prospectus, the Portfolio may be indirectly exposed to the risks associated with those investments. With respect to its investments, the CRRS Subsidiary will generally be subject to the same fundamental, non-fundamental and certain other investment restrictions as the Portfolio; however, the CRRS Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. The Portfolio and the CRRS Subsidiary may test for compliance with certain investment restrictions on a consolidated basis, except that with respect to its investments in certain securities that may involve leverage, the CRRS Subsidiary will comply with asset segregation or “earmarking” requirements to the same extent as the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a

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comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum real return. The real return sought by the Portfolio consists of both income earned on the Portfolio's investments and capital appreciation, if any, arising from increases in the market value of the Portfolio's holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in
securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.

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The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a
wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.

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Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or
sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a

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security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may
be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with

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environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign
governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.

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Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.

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Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
In addition, the Portfolio may invest in equity securities of issuers in commodity-related industries. When investing directly in equity securities, the Portfolio will not be limited to only those equity securities with any particular weighting in the Portfolio's respective benchmark index, if any. Generally, the Portfolio may consider investing directly in equity securities when derivatives on the underlying securities appear to be overvalued.    At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.
The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined

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by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,
PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for

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many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign
currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.

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Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with

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many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or
holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
A Note on the Portfolio. In light of relevant IRS guidance, as discussed above under “Tax Consequences—A Note on the Portfolio,” the Portfolio will seek to gain exposure to the commodity markets primarily through investments in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices, and through investments in the CRRS Subsidiary (as discussed below). The Portfolio may also invest in commodity-linked notes with principal and/or coupon payments linked to the value of particular commodities or commodity futures contracts, or a subset of commodities and commodities futures contracts. These notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the

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note. The value of these notes will rise or fall in response to changes in the underlying commodity, commodity futures contract, subset of commodities, subset of commodities futures contracts or commodity index.
These notes expose the Portfolio economically to movements in commodity prices. These notes also are subject to risks, such as credit, market and interest rate risks, that in general affect the values of debt securities. In addition, these notes are often leveraged, increasing the volatility of each note’s market value relative to changes in the underlying commodity, commodity futures contract or commodity index. Therefore, at the maturity of the note, the Portfolio may receive more or less principal than it originally invested. The Portfolio might receive interest payments on the note that are more or less than the stated coupon interest payments.
The Portfolio may also invest in other commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures. The value of a commodity-linked derivative investment generally is based upon the price movements of a physical commodity (such as energy, mineral, or agricultural products), a commodity futures contract, a subset of commodities, a subset of commodities futures contracts or commodity index, or other economic variable based upon changes in the value of commodities or the commodities markets.
Options transactions may be effected on exchanges or in the OTC market. When OTC options are purchased, the Portfolio’s portfolio bears the risk that the counterparty that wrote the option will be unable or unwilling to perform its obligations under the option contract. Options may also be illiquid and, in such cases, the Portfolio may have difficulty closing out its position. OTC options also may include options on baskets of specific securities.
Many swap transactions are privately negotiated agreements between the Portfolio and a counterparty to exchange or swap investment cash flows or assets at specified intervals in the future. The obligations may extend beyond one year. There is often no central exchange for swap transactions and therefore they can be less liquid investments than exchange-traded instruments. The Dodd-Frank Act and related regulatory developments require the clearing and exchange-trading of certain standardized OTC derivative instruments that the CFTC and SEC have defined as “swaps.” The CFTC has implemented mandatory exchange-trading and clearing requirements under the Dodd-Frank Act and the CFTC continues to approve contracts for central clearing. Uncleared swaps are subject to margin requirements that are being implemented on a phased-in basis. The investment adviser will continue to monitor these developments, particularly to the extent regulatory changes affect the Portfolio’s ability to enter into swap agreements.
As described below under “Characteristics and Risks of Securities and Investment Techniques—Investments in the Wholly-Owned Subsidiary,” the Portfolio may gain exposure to commodity markets by investing in the CRRS Subsidiary. It is expected that the CRRS Subsidiary will invest primarily in commodity-linked derivative instruments, including swap
agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments.
The IRS issued a revenue ruling that limits the extent to which the Portfolio may invest directly in commodity-linked swaps or certain other commodity-linked derivatives. The CRRS Subsidiary, on the other hand, may invest in these commodity-linked derivatives generally without limitation. See “Tax Consequences—A Note on the Portfolio,” above for further information.
Investments in a Wholly Owned Subsidiary
Investments in the CRRS Subsidiary are expected to provide the Portfolio with exposure to the commodity markets within the limitations of Subchapter M of the Code and recent IRS revenue rulings, as discussed above under “Tax Consequences—A Note on the Portfolio.”
It is expected that the CRRS Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments. Although the Portfolio may enter into these commodity-linked derivative instruments directly, the Portfolio will likely gain exposure to these derivative instruments indirectly by investing in the CRRS Subsidiary. To the extent that PIMCO believes that these commodity-linked derivative instruments are better suited to provide exposure to the commodities market than commodity index-linked notes, the Portfolio’s investment in the CRRS Subsidiary will likely increase. The CRRS Subsidiary will also invest in inflation-indexed securities and/or other Fixed Income Instruments, which are intended to serve as margin or collateral for the CRRS Subsidiary’s derivatives position, common and preferred securities as well as convertible securities of issuers in commodity-related industries, collateralized debt obligations, event-linked bonds and event-linked swaps. To the extent that the Portfolio invests in the CRRS Subsidiary, it may be subject to the risks associated with those derivative instruments and other securities, which are discussed elsewhere in this prospectus.
While the CRRS Subsidiary may be considered similar to an investment company, it is not registered under the 1940 Act and, unless otherwise noted in the prospectus, is not subject to all of the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the CRRS Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the CRRS Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until

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maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment
basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The limitation described in the foregoing sentence shall not apply to the Portfolio’s investment in the CRRS Subsidiary. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act, and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation

36  Prospectus | PIMCO Variable Insurance Trust

Prospectus

challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.

April 30, 2021 | PROSPECTUS  37

PIMCO Variable Insurance Trust

Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to
additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

38  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Class M shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO CommodityRealReturn® Strategy Portfolio (Consolidated)
 
 
 
 
Class M
 
 
 
 
 
 
 
 
12/31/2020
$6.37
$0.04
$(0.06)
$(0.02)
$(0.34)
$0.00
$0.00
$(0.34)
12/31/2019
5.99
0.08
0.57
0.65
(0.27)
0.00
0.00
(0.27)
12/31/2018
7.12
0.13
(1.13)
(1.00)
(0.13)
0.00
0.00
(0.13)
12/31/2017
7.83
0.11
(0.01)
0.10
(0.81)
0.00
0.00
(0.81)
12/31/2016
6.89
0.24
0.76
1.00
(0.06)
0.00
0.00
(0.06)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

39  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$6.01
1.08%
$384
1.54%
1.68%
1.19%
1.33%
0.69%
250%
6.37
10.98
490
2.46
2.57
1.19
1.30
1.26
223
5.99
(14.33)
454
2.22
2.37
1.19
1.34
1.88
237
7.12
1.94
524
1.70
1.84
1.19
1.33
1.50
157
7.83
14.62
526
1.48
1.62
1.19
1.33
3.27
206

April 30, 2021 | PROSPECTUS  40

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2105F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
Absolute Return Bond Portfolio
PIMCO Dynamic Bond Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Dynamic Bond Portfolio

Investment Objective
The Portfolio seeks maximum long-term return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.85%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.02%
Total Annual Portfolio Operating Expenses
1.02%
1
“Other Expenses” include interest expense of 0.02%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 1.00% for Administrative Class shares.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$104
$325
$563
$1,248
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 463% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in a diversified portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts, or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio intends to utilize various investment strategies in a broad array of fixed income sectors to achieve its investment objective. The Portfolio will not be constrained by management against an index. The average portfolio duration of this Portfolio will normally vary from (negative) 3 years to positive 8 years based on PIMCO’s forecast for interest rates. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio may invest in both investment-grade securities and high yield securities (“junk bonds”) subject to a maximum of 40% of its total assets in securities rated below Baa by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may also invest without limitation in securities denominated in foreign currencies and in U.S. dollar-denominated securities of foreign issuers. In addition, the Portfolio may invest up to 50% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest in such instruments without limitation subject to any applicable legal or regulatory limitation). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets. The Portfolio may also invest up to 10% of its total assets in preferred securities.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls).
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill
its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss

April 30, 2021 | PROSPECTUS  2

PIMCO Dynamic Bond Portfolio

Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s benchmark index is the 3 Month USD LIBOR Index. LIBOR (London Interbank Offered Rate) is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money (3 months) in England’s Eurodollar market.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
June 30, 2020
5.47%
Worst Quarter
March 31, 2020
-5.30%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Administrative Class Return
4.81%
4.09%
2.79%
5/2/2011
3 Month USD LIBOR Index (reflects no
deductions for fees, expenses or taxes)
0.98%
1.51%
0.93%
 
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Marc Seidner, Daniel J. Ivascyn and Mohsen Fahmi. Mr. Seidner is CIO Non-traditional Strategies, and Mr. Ivascyn is Group Chief Investment Officer. Each of Messrs. Seidner, Ivascyn and Fahmi is a Managing Director of PIMCO. Mr. Seidner has managed the Portfolio since January 2015, and Messrs. Ivascyn and Fahmi have managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

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Prospectus

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests. By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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PIMCO Variable Insurance Trust

transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.85% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.55% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.30% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Dynamic Bond
Mohsen Fahmi
9/14
Managing Director, PIMCO. Mr. Fahmi joined PIMCO in 2014 and is a generalist portfolio
manager focusing on global fixed income assets. Prior to joining PIMCO, Mr. Fahmi was with
Moore Capital Management, most recently as a senior portfolio manager and previously as
chief operating officer. Mr. Fahmi has also previously served as co-head of bond and currency
proprietary trading at Tokai Bank Europe, head of leveraged investment at Salomon Brothers
and executive director of proprietary trading at Goldman Sachs. Prior to this, he was a
proprietary trader for J.P. Morgan in both New York and London, and he also spent seven
years as an investment officer at the World Bank in Washington, D.C. He has investment
experience since 1985 and holds an MBA from Stanford University.
PIMCO Dynamic Bond
Daniel J. Ivascyn
9/14
Group Chief Investment Officer and Managing Director, PIMCO. Mr. Ivascyn joined PIMCO in
1998, previously having been associated with Bear Stearns in the asset backed securities
group, as well as T. Rowe Price and Fidelity Investments. He has investment experience since
1992 and holds an MBA in analytic finance from the University of Chicago Graduate School
of Business and a bachelor's degree in economics from Occidental College.
PIMCO Dynamic Bond
Marc Seidner
1/15
CIO Non-traditional Strategies and Managing Director, PIMCO. Mr. Seidner is head of
portfolio management in the New York office. He is also a generalist portfolio manager and a
member of the Investment Committee. He rejoined PIMCO in November 2014 after serving
as head of fixed income at GMO LLC, and previously he was a PIMCO Managing Director,
generalist portfolio manager and member of the Investment Committee until January 2014.
Prior to joining PIMCO in 2009, he was a managing director and domestic fixed income
portfolio manager at Harvard Management Company. Previously, he was director of active
core strategies at Standish Mellon Asset Management and a senior portfolio manager at
Fidelity Management and Research. He has investment experience since 1988 and holds an
undergraduate degree in economics from Boston College.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”), an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them

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Prospectus

or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the
Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;

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repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported
by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing

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out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond
the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of

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the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower
characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the

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current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that
are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a

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smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable

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generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.
The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined

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by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,
PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for

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many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign
currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.

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Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with

30  Prospectus | PIMCO Variable Insurance Trust

Prospectus

many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or
holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the

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PIMCO Variable Insurance Trust

underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment
basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

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Prospectus

Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

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Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to
additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Dynamic Bond Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$10.39
$0.29
$0.20
$0.49
$(0.29)
$0.00
$0.00
$(0.29)
12/31/2019
10.35
0.33
0.17
0.50
(0.46)
0.00
0.00
(0.46)
12/31/2018
10.54
0.32
(0.21)
0.11
(0.30)
0.00
0.00
(0.30)
12/31/2017
10.21
0.25
0.26
0.51
(0.18)
0.00
0.00
(0.18)
12/31/2016
9.92
0.29
0.17
0.46
(0.17)
0.00
0.00
(0.17)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Effective October 2, 2017, the Portfolio's Investment advisory fee was decreased by 0.05% to an annual rate of 0.55%.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.59
4.81%
$182,643
1.02%
1.02%
1.00%
1.00%
2.78%
463%
10.39
4.93
259,017
1.15
1.15
1.00
1.00
3.20
266
10.35
1.03
261,278
1.15
1.15
1.00
1.00
3.04
189
10.54
5.01
281,332
1.07(d)
1.07(d)
1.04(d)
1.04(d)
2.43
210
10.21
4.73
275,774
1.06
1.06
1.05
1.05
2.87
364

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2008F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
Absolute Return Bond Portfolio
PIMCO Dynamic Bond Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Dynamic Bond Portfolio

Investment Objective
The Portfolio seeks maximum long-term return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.85%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.02%
Total Annual Portfolio Operating Expenses
1.12%
1
“Other Expenses” include interest expense of 0.02%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 1.10% for Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$114
$356
$617
$1,363
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 463% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in a diversified portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts, or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio intends to utilize various investment strategies in a broad array of fixed income sectors to achieve its investment objective. The Portfolio will not be constrained by management against an index. The average portfolio duration of this Portfolio will normally vary from (negative) 3 years to positive 8 years based on PIMCO’s forecast for interest rates. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio may invest in both investment-grade securities and high yield securities (“junk bonds”) subject to a maximum of 40% of its total assets in securities rated below Baa by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may also invest without limitation in securities denominated in foreign currencies and in U.S. dollar-denominated securities of foreign issuers. In addition, the Portfolio may invest up to 50% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest in such instruments without limitation subject to any applicable legal or regulatory limitation). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets. The Portfolio may also invest up to 10% of its total assets in preferred securities.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls).
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill
its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss

April 30, 2021 | PROSPECTUS  2

PIMCO Dynamic Bond Portfolio

Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s benchmark index is the 3 Month USD LIBOR Index. LIBOR (London Interbank Offered Rate) is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money (3 months) in England’s Eurodollar market.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
June 30, 2020
5.44%
Worst Quarter
March 31, 2020
-5.32%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Advisor Class Return
4.70%
3.99%
2.32%
4/30/2013
3 Month USD LIBOR Index (reflects no
deductions for fees, expenses or taxes)
0.98%
1.51%
1.07%
 
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Marc Seidner, Daniel J. Ivascyn and Mohsen Fahmi. Mr. Seidner is CIO Non-traditional Strategies, and Mr. Ivascyn is Group Chief Investment Officer. Each of Messrs. Seidner, Ivascyn and Fahmi is a Managing Director of PIMCO. Mr. Seidner has managed the Portfolio since January 2015, and Messrs. Ivascyn and Fahmi have managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.85% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.55% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.30% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Dynamic Bond
Mohsen Fahmi
9/14
Managing Director, PIMCO. Mr. Fahmi joined PIMCO in 2014 and is a generalist portfolio
manager focusing on global fixed income assets. Prior to joining PIMCO, Mr. Fahmi was with
Moore Capital Management, most recently as a senior portfolio manager and previously as
chief operating officer. Mr. Fahmi has also previously served as co-head of bond and currency
proprietary trading at Tokai Bank Europe, head of leveraged investment at Salomon Brothers
and executive director of proprietary trading at Goldman Sachs. Prior to this, he was a
proprietary trader for J.P. Morgan in both New York and London, and he also spent seven
years as an investment officer at the World Bank in Washington, D.C. He has investment
experience since 1985 and holds an MBA from Stanford University.
PIMCO Dynamic Bond
Daniel J. Ivascyn
9/14
Group Chief Investment Officer and Managing Director, PIMCO. Mr. Ivascyn joined PIMCO in
1998, previously having been associated with Bear Stearns in the asset backed securities
group, as well as T. Rowe Price and Fidelity Investments. He has investment experience since
1992 and holds an MBA in analytic finance from the University of Chicago Graduate School
of Business and a bachelor's degree in economics from Occidental College.
PIMCO Dynamic Bond
Marc Seidner
1/15
CIO Non-traditional Strategies and Managing Director, PIMCO. Mr. Seidner is head of
portfolio management in the New York office. He is also a generalist portfolio manager and a
member of the Investment Committee. He rejoined PIMCO in November 2014 after serving
as head of fixed income at GMO LLC, and previously he was a PIMCO Managing Director,
generalist portfolio manager and member of the Investment Committee until January 2014.
Prior to joining PIMCO in 2009, he was a managing director and domestic fixed income
portfolio manager at Harvard Management Company. Previously, he was director of active
core strategies at Standish Mellon Asset Management and a senior portfolio manager at
Fidelity Management and Research. He has investment experience since 1988 and holds an
undergraduate degree in economics from Boston College.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

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Prospectus

From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

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Prospectus

circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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Prospectus

these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;

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bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of
the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be

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adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease
significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an

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obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored
mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the

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current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that
are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a

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smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable

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generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.
The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined

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by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,
PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for

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many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign
currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.

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Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with

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many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or
holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the

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underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment
basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

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Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

April 30, 2021 | PROSPECTUS  33

PIMCO Variable Insurance Trust

Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to
additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

34  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Dynamic Bond Portfolio
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$10.39
$0.28
$0.20
$0.48
$(0.28)
$0.00
$0.00
$(0.28)
12/31/2019
10.35
0.32
0.17
0.49
(0.45)
0.00
0.00
(0.45)
12/31/2018
10.54
0.31
(0.21)
0.10
(0.29)
0.00
0.00
(0.29)
12/31/2017
10.21
0.24
0.26
0.50
(0.17)
0.00
0.00
(0.17)
12/31/2016
9.92
0.27
0.18
0.45
(0.16)
0.00
0.00
(0.16)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Effective October 2, 2017, the Portfolio's Investment advisory fee was decreased by 0.05% to an annual rate of 0.55%.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.59
4.70%
$14,270
1.12%
1.12%
1.10%
1.10%
2.73%
463%
10.39
4.83
15,037
1.25
1.25
1.10
1.10
3.09
266
10.35
0.93
14,310
1.25
1.25
1.10
1.10
2.95
189
10.54
4.90
12,874
1.17(d)
1.17(d)
1.14(d)
1.14(d)
2.34
210
10.21
4.63
11,461
1.16
1.16
1.15
1.15
2.76
364

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2009F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
Absolute Return Bond Portfolio
PIMCO Dynamic Bond Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Dynamic Bond Portfolio

Investment Objective
The Portfolio seeks maximum long-term return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.85%
Other Expenses(1)
0.02%
Total Annual Portfolio Operating Expenses
0.87%
1
“Other Expenses” include interest expense of 0.02%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.85% for Institutional Class shares.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$89
$278
$482
$1,073
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 463% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in a diversified portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts, or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio intends to utilize various investment strategies in a broad array of fixed income sectors to achieve its investment objective. The Portfolio will not be constrained by management against an index. The average portfolio duration of this Portfolio will normally vary from (negative) 3 years to positive 8 years based on PIMCO’s forecast for interest rates. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio may invest in both investment-grade securities and high yield securities (“junk bonds”) subject to a maximum of 40% of its total assets in securities rated below Baa by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may also invest without limitation in securities denominated in foreign currencies and in U.S. dollar-denominated securities of foreign issuers. In addition, the Portfolio may invest up to 50% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest in such instruments without limitation subject to any applicable legal or regulatory limitation). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets. The Portfolio may also invest up to 10% of its total assets in preferred securities.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls).
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill
its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss

April 30, 2021 | PROSPECTUS  2

PIMCO Dynamic Bond Portfolio

Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s benchmark index is the 3 Month USD LIBOR Index. LIBOR (London Interbank Offered Rate) is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money (3 months) in England’s Eurodollar market.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class
Best Quarter
June 30, 2020
5.50%
Worst Quarter
March 31, 2020
-5.26%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Institutional Class Return
4.97%
4.25%
3.14%
4/30/2012
3 Month USD LIBOR Index (reflects no
deductions for fees, expenses or taxes)
0.98%
1.51%
0.99%
 
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Marc Seidner, Daniel J. Ivascyn and Mohsen Fahmi. Mr. Seidner is CIO Non-traditional Strategies, and Mr. Ivascyn is Group Chief Investment Officer. Each of Messrs. Seidner, Ivascyn and Fahmi is a Managing Director of PIMCO. Mr. Seidner has managed the Portfolio since January 2015, and Messrs. Ivascyn and Fahmi have managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.85% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.55% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.30% (stated as a percentage of the average daily net assets of the Portfolio).
PIMCO has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the expenses attributable to the Management Fees of series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust indirectly incurred by the Portfolio in connection with its investments in series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust to the extent the Portfolio’s Management Fees are greater than or equal to the Management Fees of the series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term.
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not:

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Prospectus

1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Dynamic Bond
Mohsen Fahmi
9/14
Managing Director, PIMCO. Mr. Fahmi joined PIMCO in 2014 and is a generalist portfolio
manager focusing on global fixed income assets. Prior to joining PIMCO, Mr. Fahmi was with
Moore Capital Management, most recently as a senior portfolio manager and previously as
chief operating officer. Mr. Fahmi has also previously served as co-head of bond and currency
proprietary trading at Tokai Bank Europe, head of leveraged investment at Salomon Brothers
and executive director of proprietary trading at Goldman Sachs. Prior to this, he was a
proprietary trader for J.P. Morgan in both New York and London, and he also spent seven
years as an investment officer at the World Bank in Washington, D.C. He has investment
experience since 1985 and holds an MBA from Stanford University.
PIMCO Dynamic Bond
Daniel J. Ivascyn
9/14
Group Chief Investment Officer and Managing Director, PIMCO. Mr. Ivascyn joined PIMCO in
1998, previously having been associated with Bear Stearns in the asset backed securities
group, as well as T. Rowe Price and Fidelity Investments. He has investment experience since
1992 and holds an MBA in analytic finance from the University of Chicago Graduate School
of Business and a bachelor's degree in economics from Occidental College.
PIMCO Dynamic Bond
Marc Seidner
1/15
CIO Non-traditional Strategies and Managing Director, PIMCO. Mr. Seidner is head of
portfolio management in the New York office. He is also a generalist portfolio manager and a
member of the Investment Committee. He rejoined PIMCO in November 2014 after serving
as head of fixed income at GMO LLC, and previously he was a PIMCO Managing Director,
generalist portfolio manager and member of the Investment Committee until January 2014.
Prior to joining PIMCO in 2009, he was a managing director and domestic fixed income
portfolio manager at Harvard Management Company. Previously, he was director of active
core strategies at Standish Mellon Asset Management and a senior portfolio manager at
Fidelity Management and Research. He has investment experience since 1988 and holds an
undergraduate degree in economics from Boston College.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

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Prospectus

From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

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Prospectus

investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder

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purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.

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Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal
Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is

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funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity
absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.

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One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore,

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the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds,

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the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and
equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.

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Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts
(“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product,

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rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the
“country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment

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opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of
another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some

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purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative

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Prospectus

instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or
price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time

April 30, 2021 | PROSPECTUS  31

PIMCO Variable Insurance Trust

when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use
solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and
reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the

April 30, 2021 | PROSPECTUS  33

PIMCO Variable Insurance Trust

Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

34  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Dynamic Bond Portfolio
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$10.39
$0.31
$0.19
$0.50
$(0.30)
$0.00
$0.00
$(0.30)
12/31/2019
10.35
0.35
0.17
0.52
(0.48)
0.00
0.00
(0.48)
12/31/2018
10.54
0.33
(0.21)
0.12
(0.31)
0.00
0.00
(0.31)
12/31/2017
10.21
0.28
0.24
0.52
(0.19)
0.00
0.00
(0.19)
12/31/2016
9.92
0.30
0.18
0.48
(0.19)
0.00
0.00
(0.19)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Effective October 2, 2017, the Portfolio’s Investment advisory fee was decreased by 0.05% to an annual rate of 0.55%.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.59
4.97%
$25,246
0.87%
0.87%
0.85%
0.85%
2.99%
463%
10.39
5.09
24,788
1.00
1.00
0.85
0.85
3.35
266
10.35
1.18
24,611
1.00
1.00
0.85
0.85
3.16
189
10.54
5.16
30,451
0.92(d)
0.92(d)
0.89(d)
0.89(d)
2.70
210
10.21
4.89
15,701
0.91
0.91
0.90
0.90
3.02
364

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2007F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: M
Absolute Return Bond Portfolio
PIMCO Dynamic Bond Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Dynamic Bond Portfolio

Investment Objective
The Portfolio seeks maximum long-term return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Class M shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Class M
Management Fees
0.85%
Distribution and/or Service (12b-1) Fees
0.45%
Other Expenses(1)
0.02%
Total Annual Portfolio Operating Expenses
1.32%
1
“Other Expenses” include interest expense of 0.02%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 1.30% for Class M shares.
Example.The Example is intended to help you compare the cost of investing in Class M shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Class M
$134
$418
$723
$1,590
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 463% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in a diversified portfolio of Fixed Income Instruments of varying maturities, which may
be represented by forwards or derivatives such as options, futures contracts, or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio intends to utilize various investment strategies in a broad array of fixed income sectors to achieve its investment objective. The Portfolio will not be constrained by management against an index. The average portfolio duration of this Portfolio will normally vary from (negative) 3 years to positive 8 years based on PIMCO’s forecast for interest rates. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio may invest in both investment-grade securities and high yield securities (“junk bonds”) subject to a maximum of 40% of its total assets in securities rated below Baa by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may also invest without limitation in securities denominated in foreign currencies and in U.S. dollar-denominated securities of foreign issuers. In addition, the Portfolio may invest up to 50% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest in such instruments without limitation subject to any applicable legal or regulatory limitation). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets. The Portfolio may also invest up to 10% of its total assets in preferred securities.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls).
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty
resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax

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PIMCO Dynamic Bond Portfolio

restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Class M shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s benchmark index is the 3 Month USD LIBOR Index. LIBOR (London Interbank Offered Rate) is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money (3 months) in England’s Eurodollar market.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Class M
Best Quarter
June 30, 2020
5.39%
Worst Quarter
March 31, 2020
-5.37%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Class M Return
4.49%
3.78%
2.69%
10/31/2014
3 Month USD LIBOR Index (reflects no
deductions for fees, expenses or taxes)
0.98%
1.51%
1.27%
 
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Marc Seidner, Daniel J. Ivascyn and Mohsen Fahmi. Mr. Seidner is CIO Non-traditional Strategies, and Mr. Ivascyn is Group Chief Investment Officer. Each of Messrs. Seidner, Ivascyn and Fahmi is a Managing Director of PIMCO. Mr. Seidner has managed the Portfolio since January 2015, and Messrs. Ivascyn and Fahmi have managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.85% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.55% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Class M shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Class M shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Class M shares at the annual rate of 0.30% (stated as a percentage of the average daily net assets of the Portfolio).
PIMCO has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the expenses attributable to the Management Fees of series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust indirectly incurred by the Portfolio in connection with its investments in series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust to the extent the Portfolio’s Management Fees are greater than or equal to the Management Fees of the series of PIMCO Funds, PIMCO Equity Series and PIMCO ETF Trust. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term.
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not:

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Prospectus

1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Dynamic Bond
Mohsen Fahmi
9/14
Managing Director, PIMCO. Mr. Fahmi joined PIMCO in 2014 and is a generalist portfolio
manager focusing on global fixed income assets. Prior to joining PIMCO, Mr. Fahmi was with
Moore Capital Management, most recently as a senior portfolio manager and previously as
chief operating officer. Mr. Fahmi has also previously served as co-head of bond and currency
proprietary trading at Tokai Bank Europe, head of leveraged investment at Salomon Brothers
and executive director of proprietary trading at Goldman Sachs. Prior to this, he was a
proprietary trader for J.P. Morgan in both New York and London, and he also spent seven
years as an investment officer at the World Bank in Washington, D.C. He has investment
experience since 1985 and holds an MBA from Stanford University.
PIMCO Dynamic Bond
Daniel J. Ivascyn
9/14
Group Chief Investment Officer and Managing Director, PIMCO. Mr. Ivascyn joined PIMCO in
1998, previously having been associated with Bear Stearns in the asset backed securities
group, as well as T. Rowe Price and Fidelity Investments. He has investment experience since
1992 and holds an MBA in analytic finance from the University of Chicago Graduate School
of Business and a bachelor's degree in economics from Occidental College.
PIMCO Dynamic Bond
Marc Seidner
1/15
CIO Non-traditional Strategies and Managing Director, PIMCO. Mr. Seidner is head of
portfolio management in the New York office. He is also a generalist portfolio manager and a
member of the Investment Committee. He rejoined PIMCO in November 2014 after serving
as head of fixed income at GMO LLC, and previously he was a PIMCO Managing Director,
generalist portfolio manager and member of the Investment Committee until January 2014.
Prior to joining PIMCO in 2009, he was a managing director and domestic fixed income
portfolio manager at Harvard Management Company. Previously, he was director of active
core strategies at Standish Mellon Asset Management and a senior portfolio manager at
Fidelity Management and Research. He has investment experience since 1988 and holds an
undergraduate degree in economics from Boston College.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Class M Shares
The Trust offers investors Class M shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Class M shares.
Distribution and/or Service (12b-1) Fees – Class M Shares. The Trust has adopted a Distribution and Servicing Plan for the Class M shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Class M shares and/or certain shareholder services to Class M shareholders at an annual rate of up to 0.25% of the Portfolio’s average daily net assets attributable to its Class M shares (the “Distribution Fee”).
The Distribution and Servicing Plan also permits the Portfolio to compensate the Distributor for providing or procuring administrative, recordkeeping, and other investor services at an annual rate with respect to the Portfolio not to exceed 0.20% of the average daily net assets of the Portfolio attributable to Class M shares (the “Servicing Fee”).
Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio’s Class M assets on an ongoing basis, over time they will increase the cost of an investment in Class M shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements. Class M shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Class M shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective
owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to

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Prospectus

insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase

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of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

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Prospectus

circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;

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bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of
the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be

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adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease
significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an

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obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored
mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the

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current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that
are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a

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smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable

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generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.
The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined

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by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,
PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for

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many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign
currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.

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Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with

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Prospectus

many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or
holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the

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underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment
basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

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Prospectus

Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

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Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to
additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Class M shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Dynamic Bond Portfolio
 
 
 
 
Class M
 
 
 
 
 
 
 
 
12/31/2020
$10.39
$0.25
$0.21
$0.46
$(0.26)
$0.00
$0.00
$(0.26)
12/31/2019
10.35
0.30
0.17
0.47
(0.43)
0.00
0.00
(0.43)
12/31/2018
10.54
0.29
(0.21)
0.08
(0.27)
0.00
0.00
(0.27)
12/31/2017
10.21
0.22
0.26
0.48
(0.15)
0.00
0.00
(0.15)
12/31/2016
9.92
0.25
0.18
0.43
(0.14)
0.00
0.00
(0.14)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Effective October 2, 2017, the Portfolio's Investment advisory fee was decreased by 0.05% to an annual rate of 0.55%.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.59
4.49%
$403
1.32%
1.32%
1.30%
1.30%
2.45%
463%
10.39
4.62
685
1.45
1.45
1.30
1.30
2.89
266
10.35
0.73
632
1.45
1.45
1.30
1.30
2.74
189
10.54
4.69
685
1.37(d)
1.37(d)
1.34(d)
1.34(d)
2.13
210
10.21
4.42
672
1.36
1.36
1.35
1.35
2.53
364

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2102F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
International Bond Portfolio
PIMCO Emerging Markets Bond Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Emerging Markets Bond Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.85%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.10%
Total Annual Portfolio Operating Expenses
1.10%
1
“Other Expenses” include interest expense of 0.10%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 1.00% for Administrative Class shares.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$112
$350
$606
$1,340
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 106% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments that are economically tied to emerging market countries, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non- U.S. public- or private-sector entities. Such instruments may be denominated in non-U.S. currencies and the U.S. dollar. The average portfolio duration of the Portfolio normally varies within two years (plus or minus) of the portfolio duration of the securities comprising the J.P. Morgan Emerging Markets Bond Index (EMBI) Global, as calculated by PIMCO, which as of February 28, 2021 was 7.71 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. The Portfolio emphasizes countries with relatively low gross national product per capita and with the potential for rapid economic growth. PIMCO will select the Portfolio’s country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors PIMCO believes to be relevant. The Portfolio likely will concentrate its investments in Asia, Africa, the Middle East, Latin America and the developing countries of Europe. The Portfolio may invest in instruments whose return is based on the return of an emerging market security or a currency of an emerging market country, such as a derivative instrument, rather than investing directly in emerging market securities or currencies.
The Portfolio may invest in both investment-grade securities and high yield securities (“junk bonds”) subject to a maximum of 15% of its total assets in securities rated below B by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may also invest directly in real estate investment trusts (“REITs”). The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Real Estate Risk:the risk that the Portfolio’s investments in Real Estate Investment Trusts (“REITs”) or real estate-linked derivative instruments will subject the Portfolio to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. A Portfolio’s investments in REITs or real estate-linked derivative instruments subject it to management and tax risks. In addition, privately traded REITs subject a Portfolio to liquidity and valuation risk

April 30, 2021 | PROSPECTUS  2

PIMCO Emerging Markets Bond Portfolio

Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance
of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The J.P. Morgan Emerging Markets Bond Index (EMBI) Global tracks total returns for U.S. Dollar denominated debt instruments issued by emerging market sovereign and quasi-sovereign entities: Brady bonds, loans, and Eurobonds.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
June 30, 2020
11.91%
Worst Quarter
March 31, 2020
-12.91%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Administrative Class Return
6.71%
7.75%
5.33%
J.P. Morgan Emerging Markets Bond Index (EMBI)
Global (reflects no deductions for fees, expenses or taxes)
5.88%
6.84%
5.97%
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Pramol Dhawan, Yacov Arnopolin and Javier Romo. Mr. Dhawan is a Managing Director of PIMCO, Mr. Arnopolin is an Executive Vice President of PIMCO, and Mr. Romo is a Senior Vice President of PIMCO. Mr. Dhawan has managed the Portfolio since June 2019, Mr. Arnopolin has managed the Portfolio since May 2017, and Mr. Romo has managed the Portfolio since May 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the NAV of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Real Estate Risk
Investments in real estate investment trusts (“REITs”) or real estate-linked derivative instruments are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. An investment in a REIT or a real estate-linked derivative instrument that is linked to the value of a REIT is subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (the “Code”). In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. Finally, private REITs are not traded on a national securities exchange. As such, these products are generally illiquid. This reduces the ability of a Portfolio to redeem its investment early. Private REITs are also generally harder to value and may bear higher fees than public REITs.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio will also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.

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Prospectus

Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the

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Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.85% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.45% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.40% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Emerging Markets Bond
Yacov Arnopolin
5/17
Executive Vice President, PIMCO. Mr. Arnopolin is an emerging markets portfolio manager in
the London office. Prior to joining PIMCO in 2016, he served as a managing director
overseeing emerging market fixed income portfolios at Goldman Sachs Asset Management.
Previously, Mr. Arnopolin worked as a portfolio manager at Fortress Investment Group. He
has investment experience since 2000 and holds a bachelor's degree in economics from
Carnegie Mellon University.
PIMCO Emerging Markets Bond
Pramol Dhawan
6/19
Managing Director, PIMCO. Mr. Dhawan is a portfolio manager in the Newport Beach office.
Prior to joining PIMCO in 2013, he was a managing director and head of emerging markets
trading for Americas at Société Générale in New York. He was previously based in London
where he headed the Central and Eastern Europe emerging markets team for the firm.
Additionally, he was a management consultant at Accenture. He has investment experience
since 2004 and holds an undergraduate degree in computer science and management
studies from the University of Nottingham.
PIMCO Emerging Markets Bond
Javier Romo
5/19
Senior Vice President, PIMCO. Prior to joining PIMCO in 2011, Mr. Romo was a Vice President
with Citigroup, where he focused on trading hard currency bonds and credit default swaps in
Latin America. Earlier in his career he was an analyst at Sandell Asset Management in
New York and before that a Vice President for Morgan Stanley focused on emerging markets
trading and local markets strategy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”), an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

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Prospectus

conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Prospectus

Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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PIMCO Variable Insurance Trust

Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them

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Prospectus

or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the
Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum real return. The real return sought by the Portfolio consists of both income earned on the Portfolio's investments and capital appreciation, if any, arising from increases in the market value of the Portfolio's holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;

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structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares.
U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary

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market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds
may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness

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of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same
underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate.

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For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be
less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”

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 Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed
from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay

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lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and

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unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.
Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in
the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.

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Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable
generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.

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The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instrument is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instrument is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of
importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,

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PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for
many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Investments in Russia. The Portfolio may invest in securities and instruments that are economically tied to Russia. Investments in Russia are subject to various risks such as, but not limited to political, economic, legal, market and currency risks, as discussed in the preceding “Emerging Market Securities” sub-section and in the “Investments in Russia” sub-section in the SAI. The risks include uncertain political and economic policies, short-term market volatility, poor accounting standards, corruption and crime, an inadequate regulatory system, regional armed conflict and unpredictable taxation. Investments in Russia are particularly subject to the risk that further economic sanctions may be imposed by the United States and/or other countries. Such sanctions – which may impact companies in many sectors, including energy, financial services and defense, among others, may negatively impact the Portfolio’s performance and/or ability to achieve its investment objective. For example, certain investments may be prohibited and/or existing investments may become illiquid (e.g., in the event that transacting in certain existing investments is prohibited), which could cause the Portfolio to sell other portfolio holdings at a disadvantageous time or price in order to meet shareholder redemptions. The Russian securities market is characterized by limited volume of trading, resulting in difficulty in obtaining accurate prices and trading. The Russian securities market, as compared to U.S. markets, has significant price volatility, less liquidity, a smaller market capitalization and a smaller number of traded securities. There may be little publicly available information about issuers. Settlement, clearing and registration of securities transactions are subject to risks. Prior to the implementation of the National Settlement Depository (“NSD”), a recognized central securities depository, there was no central registration system for equity share registration in Russia, and registration was carried out by either the issuers themselves or by registrars located throughout Russia. Title to Russian equities held through the NSD is now based on the records of the NSD and not the registrars. Although

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the implementation of the NSD has enhanced the efficiency and transparency of the Russian securities market, issues resulting in loss can still occur. Ownership of securities issued by Russian companies may be recorded by companies themselves and by registrars. In such cases, the risk is increased that the Portfolio could lose the ownership rights through fraud, negligence or oversight. While applicable Russian regulations impose liability on registrars for losses resulting from their errors, it may be difficult for the Portfolio to enforce any rights it may have against the registrar or issuer of the securities in the event of loss of share registration. In addition, issuers and registrars are still prominent in the validation and approval of documentation requirements for corporate action processing in Russia. Because the documentation requirements and approval criteria vary between registrars and issuers, there remain unclear and inconsistent market standards in the Russian market with respect to the completion and submission of corporate action elections. To the extent that a Portfolio suffers a loss relating to title or corporate actions relating to its portfolio securities, it may be difficult for the Portfolio to enforce its rights or otherwise remedy the loss. Russian securities laws may not recognize foreign nominee accounts held with a custodian bank, and therefore the custodian may be considered the ultimate owner of securities they hold for their clients. Adverse currency exchange rates are a risk and there may be a lack of available currency hedging instruments. Investments in Russia may be subject to the risk of nationalization or expropriation of assets. Oil, natural gas, metals, and timber account for a significant portion of Russia’s exports, leaving the country vulnerable to swings in world prices.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the
currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or

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other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or
all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the

April 30, 2021 | PROSPECTUS  33

PIMCO Variable Insurance Trust

Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in the Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the
value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders

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Prospectus

substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.

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PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Emerging Markets Bond Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$13.19
$0.53
$0.30
$0.83
$(0.58)
$0.00
$0.00
$(0.58)
12/31/2019
12.01
0.55
1.20
1.75
(0.57)
0.00
0.00
(0.57)
12/31/2018
13.14
0.48
(1.10)
(0.62)
(0.51)
0.00
0.00
(0.51)
12/31/2017
12.58
0.64
0.58
1.22
(0.66)
0.00
0.00
(0.66)
12/31/2016
11.70
0.64
0.90
1.54
(0.66)
0.00
0.00
(0.66)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
*
Annualized
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$13.44
6.71%
$154,896
1.10%
1.10%
1.00%
1.00%
4.12%
106%
13.19
14.77
170,681
1.02
1.02
1.00
1.00
4.28
65
12.01
(4.73)
167,673
1.01
1.01
1.00
1.00
3.86
29
13.14
9.87
210,102
1.00
1.00
1.00
1.00
4.90
35
12.58
13.31
217,567
1.00
1.00
1.00
1.00
5.19
33

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

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PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0333F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
International Bond Portfolio
PIMCO Emerging Markets Bond Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Emerging Markets Bond Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.85%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.10%
Total Annual Portfolio Operating Expenses
1.20%
1
“Other Expenses” include interest expense of 0.10%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 1.10% for Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$122
$381
$660
$1,455
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 106% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments that are economically tied to emerging market countries, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non- U.S. public- or private-sector entities. Such instruments may be denominated in non-U.S. currencies and the U.S. dollar. The average portfolio duration of the Portfolio normally varies within two years (plus or minus) of the portfolio duration of the securities comprising the J.P. Morgan Emerging Markets Bond Index (EMBI) Global, as calculated by PIMCO, which as of February 28, 2021 was 7.71 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. The Portfolio emphasizes countries with relatively low gross national product per capita and with the potential for rapid economic growth. PIMCO will select the Portfolio’s country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors PIMCO believes to be relevant. The Portfolio likely will concentrate its investments in Asia, Africa, the Middle East, Latin America and the developing countries of Europe. The Portfolio may invest in instruments whose return is based on the return of an emerging market security or a currency of an emerging market country, such as a derivative instrument, rather than investing directly in emerging market securities or currencies.
The Portfolio may invest in both investment-grade securities and high yield securities (“junk bonds”) subject to a maximum of 15% of its total assets in securities rated below B by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may also invest directly in real estate investment trusts (“REITs”). The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Real Estate Risk:the risk that the Portfolio’s investments in Real Estate Investment Trusts (“REITs”) or real estate-linked derivative instruments will subject the Portfolio to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. A Portfolio’s investments in REITs or real estate-linked derivative instruments subject it to management and tax risks. In addition, privately traded REITs subject a Portfolio to liquidity and valuation risk

April 30, 2021 | PROSPECTUS  2

PIMCO Emerging Markets Bond Portfolio

Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance
shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The J.P. Morgan Emerging Markets Bond Index (EMBI) Global tracks total returns for U.S. Dollar denominated debt instruments issued by emerging market sovereign and quasi-sovereign entities: Brady bonds, loans, and Eurobonds.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
June 30, 2020
11.88%
Worst Quarter
March 31, 2020
-12.93%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Advisor Class Return
6.60%
7.64%
5.22%
J.P. Morgan Emerging Markets Bond Index (EMBI)
Global (reflects no deductions for fees, expenses or taxes)
5.88%
6.84%
5.97%
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Pramol Dhawan, Yacov Arnopolin and Javier Romo. Mr. Dhawan is a Managing Director of PIMCO, Mr. Arnopolin is an Executive Vice President of PIMCO, and Mr. Romo is a Senior Vice President of PIMCO. Mr. Dhawan has managed the Portfolio since June 2019, Mr. Arnopolin has managed the Portfolio since May 2017, and Mr. Romo has managed the Portfolio since May 2019.

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Prospectus

Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Real Estate Risk
Investments in real estate investment trusts (“REITs”) or real estate-linked derivative instruments are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. An investment in a REIT or a real estate-linked derivative instrument that is linked to the value of a REIT is subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (the “Code”). In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. Finally, private REITs are not traded on a national securities exchange. As such, these products are generally illiquid. This reduces the ability of a Portfolio to redeem its investment early. Private REITs are also generally harder to value and may bear higher fees than public REITs.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio will also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.

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Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the

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PIMCO Variable Insurance Trust

Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.85% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.45% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.40% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Emerging Markets Bond
Yacov Arnopolin
5/17
Executive Vice President, PIMCO. Mr. Arnopolin is an emerging markets portfolio manager in
the London office. Prior to joining PIMCO in 2016, he served as a managing director
overseeing emerging market fixed income portfolios at Goldman Sachs Asset Management.
Previously, Mr. Arnopolin worked as a portfolio manager at Fortress Investment Group. He
has investment experience since 2000 and holds a bachelor's degree in economics from
Carnegie Mellon University.
PIMCO Emerging Markets Bond
Pramol Dhawan
6/19
Managing Director, PIMCO. Mr. Dhawan is a portfolio manager in the Newport Beach office.
Prior to joining PIMCO in 2013, he was a managing director and head of emerging markets
trading for Americas at Société Générale in New York. He was previously based in London
where he headed the Central and Eastern Europe emerging markets team for the firm.
Additionally, he was a management consultant at Accenture. He has investment experience
since 2004 and holds an undergraduate degree in computer science and management
studies from the University of Nottingham.
PIMCO Emerging Markets Bond
Javier Romo
5/19
Senior Vice President, PIMCO. Prior to joining PIMCO in 2011, Mr. Romo was a Vice President
with Citigroup, where he focused on trading hard currency bonds and credit default swaps in
Latin America. Earlier in his career he was an analyst at Sandell Asset Management in
New York and before that a Vice President for Morgan Stanley focused on emerging markets
trading and local markets strategy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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PIMCO Variable Insurance Trust

thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum real return. The real return sought by the Portfolio consists of both income earned on the Portfolio's investments and capital appreciation, if any, arising from increases in the market value of the Portfolio's holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;

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inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition,

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imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond
program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the

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volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools
because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.

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Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid
insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other

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asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or
losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy

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common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instrument is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instrument is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are

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applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.

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Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Investments in Russia. The Portfolio may invest in securities and instruments that are economically tied to Russia. Investments in Russia are subject to various risks such as, but not limited to political, economic, legal, market and currency risks, as discussed in the preceding “Emerging Market Securities” sub-section and in the “Investments in Russia” sub-section in the SAI. The risks include uncertain political and economic policies, short-term market volatility, poor accounting standards, corruption and crime, an inadequate regulatory system, regional armed conflict and unpredictable taxation. Investments in Russia are particularly subject to the risk that further economic sanctions may be imposed by the United States and/or other countries. Such sanctions – which may impact companies in many sectors, including energy, financial services and defense, among others, may negatively impact the Portfolio’s performance and/or ability to achieve its investment objective. For example, certain investments may be prohibited and/or existing investments may become illiquid (e.g., in the event that transacting in certain existing investments is prohibited), which could cause the Portfolio to sell other portfolio holdings at a disadvantageous time or price in order to meet shareholder redemptions. The
Russian securities market is characterized by limited volume of trading, resulting in difficulty in obtaining accurate prices and trading. The Russian securities market, as compared to U.S. markets, has significant price volatility, less liquidity, a smaller market capitalization and a smaller number of traded securities. There may be little publicly available information about issuers. Settlement, clearing and registration of securities transactions are subject to risks. Prior to the implementation of the National Settlement Depository (“NSD”), a recognized central securities depository, there was no central registration system for equity share registration in Russia, and registration was carried out by either the issuers themselves or by registrars located throughout Russia. Title to Russian equities held through the NSD is now based on the records of the NSD and not the registrars. Although the implementation of the NSD has enhanced the efficiency and transparency of the Russian securities market, issues resulting in loss can still occur. Ownership of securities issued by Russian companies may be recorded by companies themselves and by registrars. In such cases, the risk is increased that the Portfolio could lose the ownership rights through fraud, negligence or oversight. While applicable Russian regulations impose liability on registrars for losses resulting from their errors, it may be difficult for the Portfolio to enforce any rights it may have against the registrar or issuer of the securities in the event of loss of share registration. In addition, issuers and registrars are still prominent in the validation and approval of documentation requirements for corporate action processing in Russia. Because the documentation requirements and approval criteria vary between registrars and issuers, there remain unclear and inconsistent market standards in the Russian market with respect to the completion and submission of corporate action elections. To the extent that a Portfolio suffers a loss relating to title or corporate actions relating to its portfolio securities, it may be difficult for the Portfolio to enforce its rights or otherwise remedy the loss. Russian securities laws may not recognize foreign nominee accounts held with a custodian bank, and therefore the custodian may be considered the ultimate owner of securities they hold for their clients. Adverse currency exchange rates are a risk and there may be a lack of available currency hedging instruments. Investments in Russia may be subject to the risk of nationalization or expropriation of assets. Oil, natural gas, metals, and timber account for a significant portion of Russia’s exports, leaving the country vulnerable to swings in world prices.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to

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intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or
more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5%

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of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation
rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in the Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly

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PIMCO Variable Insurance Trust

with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed

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PIMCO Variable Insurance Trust

from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay
lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.

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Prospectus

The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and
unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Emerging Markets Bond Portfolio
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$13.19
$0.51
$0.31
$0.82
$(0.57)
$0.00
$0.00
$(0.57)
12/31/2019
12.01
0.54
1.19
1.73
(0.55)
0.00
0.00
(0.55)
12/31/2018
13.14
0.47
(1.10)
(0.63)
(0.50)
0.00
0.00
(0.50)
12/31/2017
12.58
0.62
0.59
1.21
(0.65)
0.00
0.00
(0.65)
12/31/2016
11.70
0.64
0.88
1.52
(0.64)
0.00
0.00
(0.64)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
*
Annualized
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$13.44
6.60%
$47,639
1.20%
1.20%
1.10%
1.10%
4.02%
106%
13.19
14.65
48,830
1.12
1.12
1.10
1.10
4.18
65
12.01
(4.83)
45,060
1.11
1.11
1.10
1.10
3.77
29
13.14
9.76
51,954
1.10
1.10
1.10
1.10
4.79
35
12.58
13.20
45,559
1.10
1.10
1.10
1.10
5.12
33

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1880F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
International Bond Portfolio
PIMCO Emerging Markets Bond Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Emerging Markets Bond Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.85%
Other Expenses(1)
0.10%
Total Annual Portfolio Operating Expenses
0.95%
1
“Other Expenses” include interest expense of 0.10%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.85% for Institutional Class shares.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$97
$303
$525
$1,166
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 106% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments that are economically tied to emerging market countries, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non- U.S. public- or private-sector entities. Such instruments may be denominated in non-U.S. currencies and the U.S. dollar. The average portfolio duration of the Portfolio normally varies within two years (plus or minus) of the portfolio duration of the securities comprising the J.P. Morgan Emerging Markets Bond Index (EMBI) Global, as calculated by PIMCO, which as of February 28, 2021 was 7.71 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. The Portfolio emphasizes countries with relatively low gross national product per capita and with the potential for rapid economic growth. PIMCO will select the Portfolio’s country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors PIMCO believes to be relevant. The Portfolio likely will concentrate its investments in Asia, Africa, the Middle East, Latin America and the developing countries of Europe. The Portfolio may invest in instruments whose return is based on the return of an emerging market security or a currency of an emerging market country, such as a derivative instrument, rather than investing directly in emerging market securities or currencies.
The Portfolio may invest in both investment-grade securities and high yield securities (“junk bonds”) subject to a maximum of 15% of its total assets in securities rated below B by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may also invest directly in real estate investment trusts (“REITs”). The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Real Estate Risk:the risk that the Portfolio’s investments in Real Estate Investment Trusts (“REITs”) or real estate-linked derivative instruments will subject the Portfolio to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. A Portfolio’s investments in REITs or real estate-linked derivative instruments subject it to management and tax risks. In addition, privately traded REITs subject a Portfolio to liquidity and valuation risk

April 30, 2021 | PROSPECTUS  2

PIMCO Emerging Markets Bond Portfolio

Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance
of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The J.P. Morgan Emerging Markets Bond Index (EMBI) Global tracks total returns for U.S. Dollar denominated debt instruments issued by emerging market sovereign and quasi-sovereign entities: Brady bonds, loans, and Eurobonds.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class
Best Quarter
June 30, 2020
11.95%
Worst Quarter
March 31, 2020
-12.87%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Institutional Class Return
6.87%
7.91%
4.72%
4/30/2012
J.P. Morgan Emerging Markets Bond
Index (EMBI) Global (reflects no
deductions for fees, expenses or taxes)
5.88%
6.84%
5.13%
 
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Pramol Dhawan, Yacov Arnopolin and Javier Romo. Mr. Dhawan is a Managing Director of PIMCO, Mr. Arnopolin is an Executive Vice President of PIMCO, and Mr. Romo is a Senior Vice President of PIMCO. Mr. Dhawan has managed the Portfolio since June 2019, Mr. Arnopolin has managed the Portfolio since May 2017, and Mr. Romo has managed the Portfolio since May 2019.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

April 30, 2021 | PROSPECTUS  7

PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

April 30, 2021 | PROSPECTUS  9

PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Real Estate Risk
Investments in real estate investment trusts (“REITs”) or real estate-linked derivative instruments are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. An investment in a REIT or a real estate-linked derivative instrument that is linked to the value of a REIT is subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (the “Code”). In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. Finally, private REITs are not traded on a national securities exchange. As such, these products are generally illiquid. This reduces the ability of a Portfolio to redeem its investment early. Private REITs are also generally harder to value and may bear higher fees than public REITs.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio will also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the

April 30, 2021 | PROSPECTUS  11

PIMCO Variable Insurance Trust

Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.85% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.45% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.40% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Emerging Markets Bond
Yacov Arnopolin
5/17
Executive Vice President, PIMCO. Mr. Arnopolin is an emerging markets portfolio manager in
the London office. Prior to joining PIMCO in 2016, he served as a managing director
overseeing emerging market fixed income portfolios at Goldman Sachs Asset Management.
Previously, Mr. Arnopolin worked as a portfolio manager at Fortress Investment Group. He
has investment experience since 2000 and holds a bachelor's degree in economics from
Carnegie Mellon University.
PIMCO Emerging Markets Bond
Pramol Dhawan
6/19
Managing Director, PIMCO. Mr. Dhawan is a portfolio manager in the Newport Beach office.
Prior to joining PIMCO in 2013, he was a managing director and head of emerging markets
trading for Americas at Société Générale in New York. He was previously based in London
where he headed the Central and Eastern Europe emerging markets team for the firm.
Additionally, he was a management consultant at Accenture. He has investment experience
since 2004 and holds an undergraduate degree in computer science and management
studies from the University of Nottingham.
PIMCO Emerging Markets Bond
Javier Romo
5/19
Senior Vice President, PIMCO. Prior to joining PIMCO in 2011, Mr. Romo was a Vice President
with Citigroup, where he focused on trading hard currency bonds and credit default swaps in
Latin America. Earlier in his career he was an analyst at Sandell Asset Management in
New York and before that a Vice President for Morgan Stanley focused on emerging markets
trading and local markets strategy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

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From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

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investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder

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purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum real return. The real return sought by the Portfolio consists of both income earned on the Portfolio's investments and capital appreciation, if any, arising from increases in the market value of the Portfolio's holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.

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Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by

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the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may
participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying

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property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real
estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and

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equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign
governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.

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Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.

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Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political
subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instrument is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instrument is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes

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in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which
they are applied may change in the discretion of PIMCO. The current factors listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or

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otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Investments in Russia. The Portfolio may invest in securities and instruments that are economically tied to Russia. Investments in Russia are subject to various risks such as, but not limited to political, economic, legal, market and currency risks, as discussed in the preceding “Emerging Market Securities” sub-section and in the “Investments in Russia” sub-section in the SAI. The risks include uncertain political and economic policies, short-term market volatility, poor accounting standards, corruption and crime, an inadequate regulatory system, regional armed conflict and unpredictable taxation. Investments in Russia are particularly subject to the risk that further economic sanctions may be imposed by the United States and/or other countries. Such sanctions – which may impact companies in many sectors, including energy, financial services and defense, among others, may negatively impact the Portfolio’s performance and/or ability to achieve its investment objective. For example, certain investments may be prohibited and/or existing investments may become illiquid (e.g., in the event that transacting in certain existing investments is prohibited), which could cause the Portfolio to sell other portfolio holdings at a disadvantageous time or price in order to meet shareholder redemptions. The Russian securities market is characterized by limited volume of trading, resulting in difficulty in obtaining accurate prices and trading. The Russian securities market, as compared to U.S. markets, has significant price volatility, less liquidity, a smaller market capitalization and a smaller number of traded securities. There may be little publicly available information about issuers. Settlement, clearing and registration of securities transactions are subject to risks. Prior to the implementation of the National Settlement Depository (“NSD”), a recognized central securities depository, there was no central registration system for equity share registration in Russia, and registration was carried out by either the issuers themselves or by registrars located throughout Russia. Title to Russian equities held through the NSD is now based on the records of the NSD and not the registrars. Although the implementation of the NSD has enhanced the efficiency and transparency of the Russian securities market, issues resulting in loss can still occur. Ownership of securities issued by Russian companies may be recorded by companies themselves and by registrars. In such cases, the risk is increased that the Portfolio could lose the ownership rights through fraud, negligence or oversight. While applicable Russian regulations impose liability on registrars for losses resulting from their errors, it may be difficult for the Portfolio to enforce any rights it may have against the registrar or issuer of the securities in the event of loss of share registration. In addition, issuers and registrars are still prominent in the validation and approval of documentation requirements for corporate action processing in Russia. Because the
documentation requirements and approval criteria vary between registrars and issuers, there remain unclear and inconsistent market standards in the Russian market with respect to the completion and submission of corporate action elections. To the extent that a Portfolio suffers a loss relating to title or corporate actions relating to its portfolio securities, it may be difficult for the Portfolio to enforce its rights or otherwise remedy the loss. Russian securities laws may not recognize foreign nominee accounts held with a custodian bank, and therefore the custodian may be considered the ultimate owner of securities they hold for their clients. Adverse currency exchange rates are a risk and there may be a lack of available currency hedging instruments. Investments in Russia may be subject to the risk of nationalization or expropriation of assets. Oil, natural gas, metals, and timber account for a significant portion of Russia’s exports, leaving the country vulnerable to swings in world prices.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the

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Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should
default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant

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impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for
unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in the Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible

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need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to
casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.

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When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose

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means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into

34  Prospectus | PIMCO Variable Insurance Trust

Prospectus

account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and
cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

April 30, 2021 | PROSPECTUS  35

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Emerging Markets Bond Portfolio
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$13.19
$0.55
$0.30
$0.85
$(0.60)
$0.00
$0.00
$(0.60)
12/31/2019
12.01
0.57
1.20
1.77
(0.59)
0.00
0.00
(0.59)
12/31/2018
13.14
0.51
(1.11)
(0.60)
(0.53)
0.00
0.00
(0.53)
12/31/2017
12.58
0.65
0.59
1.24
(0.68)
0.00
0.00
(0.68)
12/31/2016
11.70
0.67
0.88
1.55
(0.67)
0.00
0.00
(0.67)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
*
Annualized
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$13.44
6.87%
$54,693
0.95%
0.95%
0.85%
0.85%
4.26%
106%
13.19
14.94
47,874
0.87
0.87
0.85
0.85
4.42
65
12.01
(4.59)
41,154
0.86
0.86
0.85
0.85
4.08
29
13.14
10.03
34,246
0.85
0.85
0.85
0.85
5.03
35
12.58
13.48
21,191
0.85
0.85
0.85
0.85
5.37
33

April 30, 2021 | PROSPECTUS  37

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2051F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: M
International Bond Portfolio
PIMCO Emerging Markets Bond Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Emerging Markets Bond Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Class M shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Class M
Management Fees
0.85%
Distribution and/or Service (12b-1) Fees
0.45%
Other Expenses(1)
0.10%
Total Annual Portfolio Operating Expenses
1.40%
1
“Other Expenses” include interest expense of 0.10%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 1.30% for Class M shares.
Example.The Example is intended to help you compare the cost of investing in Class M shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Class M
$143
$443
$766
$1,680
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 106% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments that are economically tied to emerging market countries,
which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non- U.S. public- or private-sector entities. Such instruments may be denominated in non-U.S. currencies and the U.S. dollar. The average portfolio duration of the Portfolio normally varies within two years (plus or minus) of the portfolio duration of the securities comprising the J.P. Morgan Emerging Markets Bond Index (EMBI) Global, as calculated by PIMCO, which as of February 28, 2021 was 7.71 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. The Portfolio emphasizes countries with relatively low gross national product per capita and with the potential for rapid economic growth. PIMCO will select the Portfolio’s country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors PIMCO believes to be relevant. The Portfolio likely will concentrate its investments in Asia, Africa, the Middle East, Latin America and the developing countries of Europe. The Portfolio may invest in instruments whose return is based on the return of an emerging market security or a currency of an emerging market country, such as a derivative instrument, rather than investing directly in emerging market securities or currencies.
The Portfolio may invest in both investment-grade securities and high yield securities (“junk bonds”) subject to a maximum of 15% of its total assets in securities rated below B by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may also invest directly in real estate investment trusts (“REITs”). The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the
underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Real Estate Risk:the risk that the Portfolio’s investments in Real Estate Investment Trusts (“REITs”) or real estate-linked derivative instruments will subject the Portfolio to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. A Portfolio’s investments in REITs or real estate-linked derivative instruments subject it to management and tax risks. In addition, privately traded REITs subject a Portfolio to liquidity and valuation risk
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result

April 30, 2021 | PROSPECTUS  2

PIMCO Emerging Markets Bond Portfolio

of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table below show performance of the Portfolio’s Class M shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The J.P. Morgan Emerging Markets Bond Index (EMBI) Global tracks total returns for U.S. Dollar denominated debt instruments issued by emerging market sovereign and quasi-sovereign entities: Brady bonds, loans, and Eurobonds.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Class M
Best Quarter
June 30, 2020
11.83%
Worst Quarter
March 31, 2020
-12.97%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Class M Return
6.38%
7.43%
4.81%
11/10/2014
J.P. Morgan Emerging Markets Bond
Index (EMBI) Global (reflects no
deductions for fees, expenses or taxes)
5.88%
6.84%
5.36%
 
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Pramol Dhawan, Yacov Arnopolin and Javier Romo. Mr. Dhawan is a Managing Director of PIMCO, Mr. Arnopolin is an Executive Vice President of PIMCO, and Mr. Romo is a Senior Vice President of PIMCO. Mr. Dhawan has managed the Portfolio since June 2019, Mr. Arnopolin has managed the Portfolio since May 2017, and Mr. Romo has managed the Portfolio since May 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Real Estate Risk
Investments in real estate investment trusts (“REITs”) or real estate-linked derivative instruments are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. An investment in a REIT or a real estate-linked derivative instrument that is linked to the value of a REIT is subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (the “Code”). In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. Finally, private REITs are not traded on a national securities exchange. As such, these products are generally illiquid. This reduces the ability of a Portfolio to redeem its investment early. Private REITs are also generally harder to value and may bear higher fees than public REITs.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio will also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.

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Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the

April 30, 2021 | PROSPECTUS  11

PIMCO Variable Insurance Trust

Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.85% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.45% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Class M shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Class M shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Class M shares at the annual rate of 0.40% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Emerging Markets Bond
Yacov Arnopolin
5/17
Executive Vice President, PIMCO. Mr. Arnopolin is an emerging markets portfolio manager in
the London office. Prior to joining PIMCO in 2016, he served as a managing director
overseeing emerging market fixed income portfolios at Goldman Sachs Asset Management.
Previously, Mr. Arnopolin worked as a portfolio manager at Fortress Investment Group. He
has investment experience since 2000 and holds a bachelor's degree in economics from
Carnegie Mellon University.
PIMCO Emerging Markets Bond
Pramol Dhawan
6/19
Managing Director, PIMCO. Mr. Dhawan is a portfolio manager in the Newport Beach office.
Prior to joining PIMCO in 2013, he was a managing director and head of emerging markets
trading for Americas at Société Générale in New York. He was previously based in London
where he headed the Central and Eastern Europe emerging markets team for the firm.
Additionally, he was a management consultant at Accenture. He has investment experience
since 2004 and holds an undergraduate degree in computer science and management
studies from the University of Nottingham.
PIMCO Emerging Markets Bond
Javier Romo
5/19
Senior Vice President, PIMCO. Prior to joining PIMCO in 2011, Mr. Romo was a Vice President
with Citigroup, where he focused on trading hard currency bonds and credit default swaps in
Latin America. Earlier in his career he was an analyst at Sandell Asset Management in
New York and before that a Vice President for Morgan Stanley focused on emerging markets
trading and local markets strategy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Class M Shares
The Trust offers investors Class M shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Class M shares.
Distribution and/or Service (12b-1) Fees – Class M Shares. The Trust has adopted a Distribution and Servicing Plan for the Class M shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the 1940 Act. The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Class M shares and/or certain shareholder services to Class M shareholders at an annual rate of up to 0.25% of the Portfolio’s average daily net assets attributable to its Class M shares (the “Distribution Fee”).
The Distribution and Servicing Plan also permits the Portfolio to compensate the Distributor for providing or procuring administrative, recordkeeping, and other investor services at an annual rate with respect to the Portfolio not to exceed 0.20% of the average daily net assets of the Portfolio attributable to Class M shares (the “Servicing Fee”).
Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio’s Class M assets on an ongoing basis, over time they will increase the cost of an investment in Class M shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements. Class M shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Class M shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support
services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase

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PIMCO Variable Insurance Trust

of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum real return. The real return sought by the Portfolio consists of both income earned on the Portfolio's investments and capital appreciation, if any, arising from increases in the market value of the Portfolio's holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;

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inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition,

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imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond
program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the

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volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools
because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.

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Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid
insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other

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asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or
losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy

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common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instrument is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instrument is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are

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applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.

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Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Investments in Russia. The Portfolio may invest in securities and instruments that are economically tied to Russia. Investments in Russia are subject to various risks such as, but not limited to political, economic, legal, market and currency risks, as discussed in the preceding “Emerging Market Securities” sub-section and in the “Investments in Russia” sub-section in the SAI. The risks include uncertain political and economic policies, short-term market volatility, poor accounting standards, corruption and crime, an inadequate regulatory system, regional armed conflict and unpredictable taxation. Investments in Russia are particularly subject to the risk that further economic sanctions may be imposed by the United States and/or other countries. Such sanctions – which may impact companies in many sectors, including energy, financial services and defense, among others, may negatively impact the Portfolio’s performance and/or ability to achieve its investment objective. For example, certain investments may be prohibited and/or existing investments may become illiquid (e.g., in the event that transacting in certain existing investments is prohibited), which could cause the Portfolio to sell other portfolio holdings at a disadvantageous time or price in order to meet shareholder redemptions. The
Russian securities market is characterized by limited volume of trading, resulting in difficulty in obtaining accurate prices and trading. The Russian securities market, as compared to U.S. markets, has significant price volatility, less liquidity, a smaller market capitalization and a smaller number of traded securities. There may be little publicly available information about issuers. Settlement, clearing and registration of securities transactions are subject to risks. Prior to the implementation of the National Settlement Depository (“NSD”), a recognized central securities depository, there was no central registration system for equity share registration in Russia, and registration was carried out by either the issuers themselves or by registrars located throughout Russia. Title to Russian equities held through the NSD is now based on the records of the NSD and not the registrars. Although the implementation of the NSD has enhanced the efficiency and transparency of the Russian securities market, issues resulting in loss can still occur. Ownership of securities issued by Russian companies may be recorded by companies themselves and by registrars. In such cases, the risk is increased that the Portfolio could lose the ownership rights through fraud, negligence or oversight. While applicable Russian regulations impose liability on registrars for losses resulting from their errors, it may be difficult for the Portfolio to enforce any rights it may have against the registrar or issuer of the securities in the event of loss of share registration. In addition, issuers and registrars are still prominent in the validation and approval of documentation requirements for corporate action processing in Russia. Because the documentation requirements and approval criteria vary between registrars and issuers, there remain unclear and inconsistent market standards in the Russian market with respect to the completion and submission of corporate action elections. To the extent that a Portfolio suffers a loss relating to title or corporate actions relating to its portfolio securities, it may be difficult for the Portfolio to enforce its rights or otherwise remedy the loss. Russian securities laws may not recognize foreign nominee accounts held with a custodian bank, and therefore the custodian may be considered the ultimate owner of securities they hold for their clients. Adverse currency exchange rates are a risk and there may be a lack of available currency hedging instruments. Investments in Russia may be subject to the risk of nationalization or expropriation of assets. Oil, natural gas, metals, and timber account for a significant portion of Russia’s exports, leaving the country vulnerable to swings in world prices.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to

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intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or
more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5%

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of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation
rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in the Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly

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PIMCO Variable Insurance Trust

with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed

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PIMCO Variable Insurance Trust

from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay
lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.

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Prospectus

The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and
unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Class M shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Emerging Markets Bond Portfolio
 
 
 
 
Class M
 
 
 
 
 
 
 
 
12/31/2020
$13.19
$0.49
$0.31
$0.80
$(0.55)
$0.00
$0.00
$(0.55)
12/31/2019
12.01
0.51
1.20
1.71
(0.53)
0.00
0.00
(0.53)
12/31/2018
13.14
0.45
(1.10)
(0.65)
(0.48)
0.00
0.00
(0.48)
12/31/2017
12.58
0.60
0.58
1.18
(0.62)
0.00
0.00
(0.62)
12/31/2016
11.70
0.61
0.89
1.50
(0.62)
0.00
0.00
(0.62)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
*
Annualized
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$13.44
6.38%
$764
1.40%
1.40%
1.30%
1.30%
3.82%
106%
13.19
14.43
867
1.32
1.32
1.30
1.30
3.98
65
12.01
(5.02)
889
1.31
1.31
1.30
1.30
3.59
29
13.14
9.55
993
1.30
1.30
1.30
1.30
4.60
35
12.58
12.97
729
1.30
1.30
1.30
1.30
4.92
33

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006
INVESTMENT ADVISER AND ADMINISTRATOR

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2106F_043021


  
  
  
  
PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
International Bond Portfolio
PIMCO Global Bond Opportunities Portfolio (Unhedged)
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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PIMCO Global Bond Opportunities
Portfolio (Unhedged)

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.75%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.03%
Total Annual Portfolio Operating Expenses
0.93%
1
“Other Expenses” include interest expense of 0.03%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.90% for Administrative Class shares.
Example. The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$95
$296
$515
$1,143
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 634% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments that are economically tied to at least three countries (one of which may be the United States), which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. Securities may be denominated in major foreign currencies, baskets of foreign currencies (such as the euro), or the U.S. dollar.
PIMCO selects the Portfolio’s foreign country and currency compositions based on an evaluation of various factors, including, but not limited to, relative interest rates, exchange rates, monetary and fiscal policies, and trade and current account balances. The Portfolio may invest, without limitation, in securities and instruments that are economically tied to emerging market countries. The Portfolio normally invests at least 25% of its net assets in instruments that are economically tied to foreign (non-U.S.) countries. The average portfolio duration of this Portfolio normally varies between two and eight years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio invests primarily in investment grade debt securities, but may invest up to 20% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus  

Prospectus

Interest Rate Risk: the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk: the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk: the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk: the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk: the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk: the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk: the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk: the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill
its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk: the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk: the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk: the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk: the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk: the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk: the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk: the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss

April 30, 2021 | PROSPECTUS  2

PIMCO Global Bond Opportunities Portfolio (Unhedged)

Management Risk: the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk: the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk: the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s broad-based securities market index is the Bloomberg Barclays Global Aggregate (USD Unhedged) Index. The Bloomberg Barclays Global Aggregate (USD Unhedged) Index provides a broad-based measure of the global investment-grade fixed income markets. The three major components of this index are the
U.S. Aggregate, the Pan-European Aggregate, and the Asian-Pacific Aggregate Indices. The index also includes Eurodollar and Euro-Yen corporate bonds, Canadian Government securities, and USD investment grade 144A securities. It is not possible to invest directly in an unmanaged index.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class   
Best Quarter
June 30, 2020
6.53%
Worst Quarter
December 31, 2016
-6.16%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Administrative Class Return
10.12%
4.82%
2.72%
Bloomberg Barclays Global Aggregate (USD Unhedged)
Index (reflects no deductions for fees, expenses or
taxes)
9.20%
4.79%
2.83%
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Balls, Sachin Gupta and Lorenzo Pagani. Mr. Balls is CIO Global Fixed Income and a Managing Director of PIMCO. Mr. Gupta and Dr. Pagani are Managing Directors of PIMCO. Messrs. Balls and Gupta and Dr. Pagani have jointly and primarily managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

April 30, 2021 | PROSPECTUS  7

PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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PIMCO Variable Insurance Trust

transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.75% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee. The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee. The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager
Since
Recent Professional Experience
PIMCO Global Bond Opportunities (Unhedged)
Andrew Balls
9/14
CIO Global Fixed Income and Managing Director, PIMCO. He joined PIMCO in 2006 and is a
member of the Investment Committee and head of European portfolio management. Prior to
joining PIMCO, he spent eight years at the Financial Times, most recently as editor of the
U.S. Lex column and as chief economics correspondent in Washington, D.C.
PIMCO Global Bond Opportunities (Unhedged)
Sachin Gupta
9/14
Managing Director, PIMCO. Mr. Gupta joined PIMCO in 2003. He has previously managed
European LDI portfolios and served on the global portfolio management team in PIMCO's
Singapore office. Mr. Gupta has focused on investments in government bonds, sovereign credit
derivatives and interest rate derivatives across developed markets. Prior to joining PIMCO, Mr.
Gupta was in the fixed income and currency derivatives group at ABN AMRO Bank. He has
investment experience since 1998 and holds an MBA from XLRI, India.
PIMCO Global Bond Opportunities (Unhedged)
Lorenzo Pagani
9/14
Managing Director, PIMCO. Dr. Pagani joined PIMCO in 2004 and is a portfolio manager in
PIMCO's Munich office and head of the European government bond and European rates desk.
Prior to joining PIMCO, he was with the nuclear engineering department at the Massachusetts
Institute of Technology and with Procter & Gamble in Italy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares. The Trust has adopted, pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”), an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements. Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments. PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

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conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them

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or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the
Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;

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structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares.
U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary

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market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds
may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness

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of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same
underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate.

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For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be
less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”

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  Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a
portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including

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convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions. Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights. Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income
Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other

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collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities. The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the
security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future

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economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions. The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the
value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination. Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to

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withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives
strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.  A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.  Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.  The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.

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Liquidity Risk.   Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.   Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in the Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.  Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.  In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the
markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.  Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.

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ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling
a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

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Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

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Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to
additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

34  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Global Bond Opportunities Portfolio (Unhedged)
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$11.35
$0.20
$0.92
$1.12
$(0.28)
$0.00
$0.00
$(0.28)
12/31/2019
10.96
0.26
0.40
0.66
(0.27)
0.00
0.00
(0.27)
12/31/2018
12.29
0.25
(0.77)
(0.52)
(0.74)
(0.03)
(0.04)
(0.81)
12/31/2017
11.54
0.19
0.80
0.99
(0.24)
0.00
0.00
(0.24)
12/31/2016
11.26
0.23
0.23
0.46
(0.18)
0.00
0.00
(0.18)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$12.19
10.12%
$152,386
0.93%
0.93%
0.90%
0.90%
1.73%
634%
11.35
6.12
159,222
1.03
1.03
0.90
0.90
2.31
382
10.96
(4.19)
166,921
0.99
0.99
0.90
0.90
2.12
255
12.29
8.63
198,189
0.96
0.96
0.90
0.90
1.58
339
11.54
4.04
197,606
0.92
0.92
0.90
0.90
1.93
676

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securities  are those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securities  are those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),  are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

  
  
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0336S_043021


  
  
  
  
PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
International Bond Portfolio
PIMCO Global Bond Opportunities Portfolio (Unhedged)
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
Page
1
1
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12
14
16
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A-1


 
  
PIMCO Global Bond Opportunities
Portfolio (Unhedged)

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.75%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.03%
Total Annual Portfolio Operating Expenses
1.03%
1
“Other Expenses” include interest expense of 0.03%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 1.00% for Advisor Class shares.
Example. The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$105
$328
$569
$1,259
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 634% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments that are economically tied to at least three countries (one of which may be the United States), which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. Securities may be denominated in major foreign currencies, baskets of foreign currencies (such as the euro), or the U.S. dollar.
PIMCO selects the Portfolio’s foreign country and currency compositions based on an evaluation of various factors, including, but not limited to, relative interest rates, exchange rates, monetary and fiscal policies, and trade and current account balances. The Portfolio may invest, without limitation, in securities and instruments that are economically tied to emerging market countries. The Portfolio normally invests at least 25% of its net assets in instruments that are economically tied to foreign (non-U.S.) countries. The average portfolio duration of this Portfolio normally varies between two and eight years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio invests primarily in investment grade debt securities, but may invest up to 20% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus  

Prospectus

Interest Rate Risk: the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk: the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk: the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk: the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk: the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk: the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk: the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk: the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill
its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk: the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk: the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk: the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk: the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk: the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk: the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk: the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss

April 30, 2021 | PROSPECTUS  2

PIMCO Global Bond Opportunities Portfolio (Unhedged)

Management Risk: the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk: the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk: the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s broad-based securities market index is the Bloomberg Barclays Global Aggregate (USD Unhedged) Index. The Bloomberg Barclays Global Aggregate (USD Unhedged) Index provides a broad-based measure of the global investment-grade fixed income markets. The three major components of this index are the
U.S. Aggregate, the Pan-European Aggregate, and the Asian-Pacific Aggregate Indices. The index also includes Eurodollar and Euro-Yen corporate bonds, Canadian Government securities, and USD investment grade 144A securities. It is not possible to invest directly in an unmanaged index.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class   
Best Quarter
June 30, 2020
6.50%
Worst Quarter
December 31, 2016
-6.18%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Advisor Class Return
10.01%
4.71%
2.61%
Bloomberg Barclays Global Aggregate (USD Unhedged)
Index (reflects no deductions for fees, expenses or
taxes)
9.20%
4.79%
2.83%
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Balls, Sachin Gupta and Lorenzo Pagani. Mr. Balls is CIO Global Fixed Income and a Managing Director of PIMCO. Mr. Gupta and Dr. Pagani are Managing Directors of PIMCO. Messrs. Balls and Gupta and Dr. Pagani have jointly and primarily managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.75% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee. The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee. The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager
Since
Recent Professional Experience
PIMCO Global Bond Opportunities (Unhedged)
Andrew Balls
9/14
CIO Global Fixed Income and Managing Director, PIMCO. He joined PIMCO in 2006 and is a
member of the Investment Committee and head of European portfolio management. Prior to
joining PIMCO, he spent eight years at the Financial Times, most recently as editor of the
U.S. Lex column and as chief economics correspondent in Washington, D.C.
PIMCO Global Bond Opportunities (Unhedged)
Sachin Gupta
9/14
Managing Director, PIMCO. Mr. Gupta joined PIMCO in 2003. He has previously managed
European LDI portfolios and served on the global portfolio management team in PIMCO's
Singapore office. Mr. Gupta has focused on investments in government bonds, sovereign credit
derivatives and interest rate derivatives across developed markets. Prior to joining PIMCO, Mr.
Gupta was in the fixed income and currency derivatives group at ABN AMRO Bank. He has
investment experience since 1998 and holds an MBA from XLRI, India.
PIMCO Global Bond Opportunities (Unhedged)
Lorenzo Pagani
9/14
Managing Director, PIMCO. Dr. Pagani joined PIMCO in 2004 and is a portfolio manager in
PIMCO's Munich office and head of the European government bond and European rates desk.
Prior to joining PIMCO, he was with the nuclear engineering department at the Massachusetts
Institute of Technology and with Procter & Gamble in Italy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares. The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements. Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments. PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

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Prospectus

From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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PIMCO Variable Insurance Trust

thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;

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inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition,

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imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond
program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the

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volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools
because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.

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Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid
insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other

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asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or
losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy

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common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions. Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights. Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical

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service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities. The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.

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Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions. The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which
involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination. Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro

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cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates,
commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.  A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.  Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.  The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to

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the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.  Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.  Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in the Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.  Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.  In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited
to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.  Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.

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Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will
decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to

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$1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established
secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In

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PIMCO Variable Insurance Trust

such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in
achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or

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unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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PIMCO Variable Insurance Trust

The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Global Bond Opportunities Portfolio (Unhedged)
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$11.35
$0.19
$0.92
$1.11
$(0.27)
$0.00
$0.00
$(0.27)
12/31/2019
10.96
0.25
0.40
0.65
(0.26)
0.00
0.00
(0.26)
12/31/2018
12.29
0.24
(0.77)
(0.53)
(0.73)
(0.03)
(0.04)
(0.80)
12/31/2017
11.54
0.18
0.80
0.98
(0.23)
0.00
0.00
(0.23)
12/31/2016
11.26
0.22
0.23
0.45
(0.17)
0.00
0.00
(0.17)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$12.19
10.01%
$23,451
1.03%
1.03%
1.00%
1.00%
1.63%
634%
11.35
6.02
23,386
1.13
1.13
1.00
1.00
2.21
382
10.96
(4.29)
23,856
1.09
1.09
1.00
1.00
2.01
255
12.29
8.52
29,267
1.06
1.06
1.00
1.00
1.47
339
11.54
3.94
31,111
1.02
1.02
1.00
1.00
1.82
676

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securities  are those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securities  are those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),  are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

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Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

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PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

  
  
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1881F_043021


  
  
  
  
PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
International Bond Portfolio
PIMCO Global Bond Opportunities Portfolio (Unhedged)
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


 
  
PIMCO Global Bond Opportunities
Portfolio (Unhedged)

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.75%
Other Expenses(1)
0.03%
Total Annual Portfolio Operating Expenses
0.78%
1
“Other Expenses” include interest expense of 0.03%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.75% for Institutional Class shares.
Example. The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$80
$249
$433
$966
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 634% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments that are economically tied to at least three countries (one of which may be the United States), which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. Securities may be denominated in major foreign currencies, baskets of foreign currencies (such as the euro), or the U.S. dollar.
PIMCO selects the Portfolio’s foreign country and currency compositions based on an evaluation of various factors, including, but not limited to, relative interest rates, exchange rates, monetary and fiscal policies, and trade and current account balances. The Portfolio may invest, without limitation, in securities and instruments that are economically tied to emerging market countries. The Portfolio normally invests at least 25% of its net assets in instruments that are economically tied to foreign (non-U.S.) countries. The average portfolio duration of this Portfolio normally varies between two and eight years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio invests primarily in investment grade debt securities, but may invest up to 20% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus  

Prospectus

Interest Rate Risk: the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk: the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk: the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk: the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk: the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk: the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk: the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk: the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill
its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk: the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk: the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk: the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk: the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk: the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk: the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk: the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss

April 30, 2021 | PROSPECTUS  2

PIMCO Global Bond Opportunities Portfolio (Unhedged)

Management Risk: the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk: the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk: the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s broad-based securities market index is the Bloomberg Barclays Global Aggregate (USD Unhedged) Index. The Bloomberg Barclays Global Aggregate (USD Unhedged) Index provides a broad-based measure of the global investment-grade fixed income markets. The three major components of this index are the
U.S. Aggregate, the Pan-European Aggregate, and the Asian-Pacific Aggregate Indices. The index also includes Eurodollar and Euro-Yen corporate bonds, Canadian Government securities, and USD investment grade 144A securities. It is not possible to invest directly in an unmanaged index.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class   
Best Quarter
June 30, 2020
6.57%
Worst Quarter
December 31, 2016
-6.12%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Institutional Class Return
10.28%
4.98%
2.87%
Bloomberg Barclays Global Aggregate (USD Unhedged)
Index (reflects no deductions for fees, expenses or
taxes)
9.20%
4.79%
2.83%
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Balls, Sachin Gupta and Lorenzo Pagani. Mr. Balls is CIO Global Fixed Income and a Managing Director of PIMCO. Mr. Gupta and Dr. Pagani are Managing Directors of PIMCO. Messrs. Balls and Gupta and Dr. Pagani have jointly and primarily managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please

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Prospectus

refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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PIMCO Variable Insurance Trust

transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.75% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee. The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee. The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager
Since
Recent Professional Experience
PIMCO Global Bond Opportunities (Unhedged)
Andrew Balls
9/14
CIO Global Fixed Income and Managing Director, PIMCO. He joined PIMCO in 2006 and is a
member of the Investment Committee and head of European portfolio management. Prior to
joining PIMCO, he spent eight years at the Financial Times, most recently as editor of the
U.S. Lex column and as chief economics correspondent in Washington, D.C.
PIMCO Global Bond Opportunities (Unhedged)
Sachin Gupta
9/14
Managing Director, PIMCO. Mr. Gupta joined PIMCO in 2003. He has previously managed
European LDI portfolios and served on the global portfolio management team in PIMCO's
Singapore office. Mr. Gupta has focused on investments in government bonds, sovereign credit
derivatives and interest rate derivatives across developed markets. Prior to joining PIMCO, Mr.
Gupta was in the fixed income and currency derivatives group at ABN AMRO Bank. He has
investment experience since 1998 and holds an MBA from XLRI, India.
PIMCO Global Bond Opportunities (Unhedged)
Lorenzo Pagani
9/14
Managing Director, PIMCO. Dr. Pagani joined PIMCO in 2004 and is a portfolio manager in
PIMCO's Munich office and head of the European government bond and European rates desk.
Prior to joining PIMCO, he was with the nuclear engineering department at the Massachusetts
Institute of Technology and with Procter & Gamble in Italy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements. Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments. PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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PIMCO Variable Insurance Trust

per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

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investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder

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purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.

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Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by

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the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may
participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying

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property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real
estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and

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equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign
governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.

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Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.

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Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions. Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights. Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political
subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes

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in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities. The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which
they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or

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otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions. The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant
foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination. Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but

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only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in
“Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.  A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.  Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.  The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.  Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.  Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in the Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.  Because the markets for certain derivative instruments (including markets located in foreign countries) are

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relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.  In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.  Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies
involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.

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PIMCO Variable Insurance Trust

Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled
vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no

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added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a
portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not

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evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents,
custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Global Bond Opportunities Portfolio (Unhedged)
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$11.35
$0.21
$0.93
$1.14
$(0.30)
$0.00
$0.00
$(0.30)
12/31/2019
10.96
0.27
0.41
0.68
(0.29)
0.00
0.00
(0.29)
12/31/2018
12.29
0.27
(0.77)
(0.50)
(0.76)
(0.03)
(0.04)
(0.83)
12/31/2017
11.54
0.21
0.80
1.01
(0.26)
0.00
0.00
(0.26)
12/31/2016
11.26
0.24
0.24
0.48
(0.20)
0.00
0.00
(0.20)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
*
Annualized
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$12.19
10.28%
$11,120
0.78%
0.78%
0.75%
0.75%
1.87%
634%
11.35
6.28
9,625
0.88
0.88
0.75
0.75
2.46
382
10.96
(4.05)
9,561
0.84
0.84
0.75
0.75
2.27
255
12.29
8.79
10,067
0.81
0.81
0.75
0.75
1.73
339
11.54
4.20
9,237
0.77
0.77
0.75
0.75
2.03
676

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securities  are those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securities  are those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),  are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

  
  
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1876S_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
International Bond Portfolio
PIMCO Global Core Bond (Hedged) Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Global Core Bond (Hedged) Portfolio

Investment Objective
The Portfolio seeks total return which exceeds that of its benchmark.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.56%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.07%
Total Annual Portfolio Operating Expenses
0.78%
1
“Other Expenses” include interest expense of 0.07%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.71% for Administrative Class shares.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$80
$249
$433
$966
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 665% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments that are economically tied to at least three countries (one of which may be the United States), which may be represented by forwards or derivatives such as options, futures contracts, or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities.
PIMCO selects the Portfolio’s foreign country and currency compositions based on an evaluation of various factors, including, but not limited to, relative interest rates, exchange rates, monetary and fiscal policies, and trade and current account balances. The Portfolio may invest without limitation in securities denominated in foreign currencies and in U.S. dollar-denominated securities of foreign issuers. The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to within 5% (plus or minus) of the foreign currency exposure of the Bloomberg Barclays Global Aggregate (USD Hedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 0.04%. The Portfolio may invest in securities and instruments that are economically tied to emerging market countries in an amount up to 5% of its total assets above the level of those types of securities and instruments represented in the Bloomberg Barclays Global Aggregate (USD Hedged) Index. The Portfolio may also invest up to 5% of its total assets in preferred securities. In addition, the Portfolio may invest in both investment-grade securities and high yield securities (“junk bonds”) subject to a maximum of 10% of its total assets in securities rated below BBB by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The average portfolio duration of this Portfolio normally varies within 1.5 years (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays Global Aggregate (USD Hedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 7.27 years. In addition, the average U.S. portfolio duration of this Portfolio normally varies within 1 year (plus or minus) of the U.S. portfolio duration of the securities comprising the Bloomberg Barclays Global Aggregate (USD Hedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 6.11 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates or improving credit fundamentals for a particular sector or security.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Small Portfolio Risk:the risk that a smaller Portfolio may not achieve investment or trading efficiencies. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the
lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk

April 30, 2021 | PROSPECTUS  2

PIMCO Global Core Bond (Hedged) Portfolio

Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio's broad-based securities market index is the Bloomberg Barclays Global Aggregate (USD Hedged) Index. The Bloomberg Barclays Global Aggregate (USD Hedged) Index provides a broad-based measure of the global investment-grade fixed income markets hedged to U.S. dollars. The three major components of this index are the U.S. Aggregate, the Pan-European Aggregate, and the Asian-Pacific Aggregate Indices. The index also includes Eurodollar and Euro-Yen corporate bonds, Canadian Government securities, and USD investment grade 144A securities. It is not possible to invest directly in an unmanaged index. 
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
June 30, 2020
4.32%
Worst Quarter
June 30, 2013
-4.34%

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Administrative Class Return
8.10%
5.59%
2.34%
5/2/2011
Bloomberg Barclays Global Aggregate
(USD Hedged) Index (reflects no
deductions for fees, expenses or taxes)
5.58%
4.49%
4.25%
 
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Balls, Sachin Gupta and Lorenzo Pagani. Mr. Balls is CIO Global Fixed Income and a Managing Director of PIMCO. Mr. Gupta and Dr. Pagani are Managing Directors of PIMCO. Mr. Balls has managed the Portfolio since October 2011, Mr. Gupta has managed the Portfolio since September 2014, and Dr. Pagani has managed the Portfolio since October 2016.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Small Portfolio Risk
A smaller Portfolio may not grow to or maintain an economically viable size to achieve investment or trading efficiencies, which may negatively impact performance and/or force the Portfolio to liquidate. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchases or redemptions.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.

April 30, 2021 | PROSPECTUS  7

PIMCO Variable Insurance Trust

In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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PIMCO Variable Insurance Trust

transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.56% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.31% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Global Core Bond (Hedged)
Andrew Balls
10/11
CIO Global Fixed Income and Managing Director, PIMCO. He joined PIMCO in 2006 and is a
member of the Investment Committee and head of European portfolio management. Prior to
joining PIMCO, he spent eight years at the Financial Times, most recently as editor of the
U.S. Lex column and as chief economics correspondent in Washington, D.C.
PIMCO Global Core Bond (Hedged)
Sachin Gupta
9/14
Managing Director, PIMCO. Mr. Gupta joined PIMCO in 2003. He has previously managed
European LDI portfolios and served on the global portfolio management team in PIMCO's
Singapore office. Mr. Gupta has focused on investments in government bonds, sovereign
credit derivatives and interest rate derivatives across developed markets. Prior to joining
PIMCO, Mr. Gupta was in the fixed income and currency derivatives group at ABN AMRO
Bank. He has investment experience since 1998 and holds an MBA from XLRI, India.
PIMCO Global Core Bond (Hedged)
Lorenzo Pagani
10/16
Managing Director, PIMCO. Dr. Pagani joined PIMCO in 2004 and is a portfolio manager in
PIMCO's Munich office and head of the European government bond and European rates
desk. Prior to joining PIMCO, he was with the nuclear engineering department at the
Massachusetts Institute of Technology and with Procter & Gamble in Italy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”), an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

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conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them

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or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the
Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;

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structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares.
U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary

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market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds
may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness

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of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same
underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate.

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For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be
less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”

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  Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a
portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including

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convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income
Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other

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collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the
security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future

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economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the
value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to

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withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives
strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.

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Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the
markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.

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ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling
a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

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Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

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Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to
additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

34  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Global Core Bond (Hedged) Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$9.93
$0.20
$0.57
$0.77
$(0.62)
$0.00
$0.00
$(0.62)
12/31/2019
9.41
0.21
0.53
0.74
(0.22)
0.00
0.00
(0.22)
12/31/2018
9.47
0.18
(0.08)
0.10
(0.16)
0.00
0.00
(0.16)
12/31/2017
9.21
0.15
0.24
0.39
(0.13)
0.00
0.00
(0.13)
12/31/2016
8.77
0.21
0.38
0.59
(0.15)
0.00
0.00
(0.15)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Effective October 21, 2016, the Portfolio’s Investment advisory fee was decreased by 0.15% to an annual rate of 0.25% and the Portfolio’s supervisory and administrative fee was decreased by 0.04% to an annual rate of 0.31%

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.08
8.10%
$92,145
0.78%
0.78%
0.71%
0.71%
1.98%
665%
9.93
7.88
97,876
0.84
0.84
0.71
0.71
2.19
375
9.41
1.05
110,302
0.76
0.76
0.71
0.71
1.87
327
9.47
4.29
107,869
0.76
0.76
0.71
0.71
1.61
292
9.21
6.78
107,052
0.91(d)
0.91(d)
0.86(d)
0.86(d)
2.31
342

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2005F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
International Bond Portfolio
PIMCO Global Core Bond (Hedged) Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
Page
1
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35
A-1


PIMCO Global Core Bond (Hedged) Portfolio

Investment Objective
The Portfolio seeks total return which exceeds that of its benchmark.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.56%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.07%
Total Annual Portfolio Operating Expenses
0.88%
1
“Other Expenses” include interest expense of 0.07%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.81% Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$90
$281
$488
$1,084
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 665% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments that are economically tied to at least three countries (one of which may be the United States), which may be represented by forwards or derivatives such as options, futures contracts, or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities.
PIMCO selects the Portfolio’s foreign country and currency compositions based on an evaluation of various factors, including, but not limited to, relative interest rates, exchange rates, monetary and fiscal policies, and trade and current account balances. The Portfolio may invest without limitation in securities denominated in foreign currencies and in U.S. dollar-denominated securities of foreign issuers. The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to within 5% (plus or minus) of the foreign currency exposure of the Bloomberg Barclays Global Aggregate (USD Hedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 0.04%. The Portfolio may invest in securities and instruments that are economically tied to emerging market countries in an amount up to 5% of its total assets above the level of those types of securities and instruments represented in the Bloomberg Barclays Global Aggregate (USD Hedged) Index. The Portfolio may also invest up to 5% of its total assets in preferred securities. In addition, the Portfolio may invest in both investment-grade securities and high yield securities (“junk bonds”) subject to a maximum of 10% of its total assets in securities rated below BBB by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The average portfolio duration of this Portfolio normally varies within 1.5 years (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays Global Aggregate (USD Hedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 7.27 years. In addition, the average U.S. portfolio duration of this Portfolio normally varies within 1 year (plus or minus) of the U.S. portfolio duration of the securities comprising the Bloomberg Barclays Global Aggregate (USD Hedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 6.11 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates or improving credit fundamentals for a particular sector or security.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Small Portfolio Risk:the risk that a smaller Portfolio may not achieve investment or trading efficiencies. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the
lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk

April 30, 2021 | PROSPECTUS  2

PIMCO Global Core Bond (Hedged) Portfolio

Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio's broad-based securities market index is the Bloomberg Barclays Global Aggregate (USD Hedged) Index. The Bloomberg Barclays Global Aggregate (USD Hedged) Index provides a broad-based measure of the global investment-grade fixed income markets hedged to U.S. dollars. The three major components of this index are the U.S. Aggregate, the Pan-European Aggregate, and the Asian-Pacific Aggregate Indices. The index also includes Eurodollar and Euro-Yen corporate bonds, Canadian Government securities, and USD investment grade 144A securities. It is not possible to invest directly in an unmanaged index. 
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class (1)
Best Quarter
June 30, 2020
4.32%
Worst Quarter
June 30, 2013
-4.34%

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Administrative Class Return
8.10%
5.59%
2.34%
5/2/2011
Bloomberg Barclays Global Aggregate
(USD Hedged) Index (reflects no
deductions for fees, expenses or taxes)
5.58%
4.49%
4.25%
 
(1)
Since the Portfolio’s Advisor Class has not commenced operations as of the date of this prospectus, the bar chart and the table show performance of the Portfolio’s Administrative Class shares, which are offered in a separate prospectus. Although the Advisor Class and Administrative Class would have substantially similar annual returns (because they represent interests in the same portfolio of securities). Advisor Class and Administrative Class performance would differ to the exten that the Advisor Class has lower expenses.
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Balls, Sachin Gupta and Lorenzo Pagani. Mr. Balls is CIO Global Fixed Income and a Managing Director of PIMCO. Mr. Gupta and Dr. Pagani are Managing Directors of PIMCO. Mr. Balls has managed the Portfolio since October 2011, Mr. Gupta has managed the Portfolio since September 2014, and Dr. Pagani has managed the Portfolio since October 2016.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your
salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Small Portfolio Risk
A smaller Portfolio may not grow to or maintain an economically viable size to achieve investment or trading efficiencies, which may negatively impact performance and/or force the Portfolio to liquidate. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchases or redemptions.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases

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result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.

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In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.

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In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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PIMCO Variable Insurance Trust

transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.56% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.31% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Global Core Bond (Hedged)
Andrew Balls
10/11
CIO Global Fixed Income and Managing Director, PIMCO. He joined PIMCO in 2006 and is a
member of the Investment Committee and head of European portfolio management. Prior to
joining PIMCO, he spent eight years at the Financial Times, most recently as editor of the
U.S. Lex column and as chief economics correspondent in Washington, D.C.
PIMCO Global Core Bond (Hedged)
Sachin Gupta
9/14
Managing Director, PIMCO. Mr. Gupta joined PIMCO in 2003. He has previously managed
European LDI portfolios and served on the global portfolio management team in PIMCO's
Singapore office. Mr. Gupta has focused on investments in government bonds, sovereign
credit derivatives and interest rate derivatives across developed markets. Prior to joining
PIMCO, Mr. Gupta was in the fixed income and currency derivatives group at ABN AMRO
Bank. He has investment experience since 1998 and holds an MBA from XLRI, India.
PIMCO Global Core Bond (Hedged)
Lorenzo Pagani
10/16
Managing Director, PIMCO. Dr. Pagani joined PIMCO in 2004 and is a portfolio manager in
PIMCO's Munich office and head of the European government bond and European rates
desk. Prior to joining PIMCO, he was with the nuclear engineering department at the
Massachusetts Institute of Technology and with Procter & Gamble in Italy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio.

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment
medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading

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PIMCO Variable Insurance Trust

on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization
companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing
sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments

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may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.

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Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;

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repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported
by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing

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out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond
the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of

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the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower
characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the

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current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that
are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in

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the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable

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generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.
The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined

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by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,
PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for

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many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign
currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.

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Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with

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many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or
holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the

April 30, 2021 | PROSPECTUS  31

PIMCO Variable Insurance Trust

underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment
basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

April 30, 2021 | PROSPECTUS  33

PIMCO Variable Insurance Trust

Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to
additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

34  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Global Core Bond (Hedged) Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$9.93
$0.20
$0.57
$0.77
$(0.62)
$0.00
$0.00
$(0.62)
12/31/2019
9.41
0.21
0.53
0.74
(0.22)
0.00
0.00
(0.22)
12/31/2018
9.47
0.18
(0.08)
0.10
(0.16)
0.00
0.00
(0.16)
12/31/2017
9.21
0.15
0.24
0.39
(0.13)
0.00
0.00
(0.13)
12/31/2016
8.77
0.21
0.38
0.59
(0.15)
0.00
0.00
(0.15)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Effective October 21, 2016, the Portfolio’s Investment advisory fee was decreased by 0.15% to an annual rate of 0.25% and the Portfolio’s supervisory and administrative fee was decreased by 0.04% to an annual rate of 0.31%

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.08
8.10%
$92,145
0.78%
0.78%
0.71%
0.71%
1.98%
665%
9.93
7.88
97,876
0.84
0.84
0.71
0.71
2.19
375
9.41
1.05
110,302
0.76
0.76
0.71
0.71
1.87
327
9.47
4.29
107,869
0.76
0.76
0.71
0.71
1.61
292
9.21
6.78
107,052
0.91(d)
0.91(d)
0.86(d)
0.86(d)
2.31
342

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2006S_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
International Bond Portfolio
PIMCO Global Core Bond (Hedged) Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Global Core Bond (Hedged) Portfolio

Investment Objective
The Portfolio seeks total return which exceeds that of its benchmark.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.56%
Other Expenses(1)
0.07%
Total Annual Portfolio Operating Expenses
0.63%
1
“Other Expenses” include interest expense of 0.07%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.56% for Institutional Class shares.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$64
$202
$351
$786
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 665% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments that are economically tied to at least three countries (one of which may be the United States), which may be represented by forwards or derivatives such as options, futures contracts, or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities.
PIMCO selects the Portfolio’s foreign country and currency compositions based on an evaluation of various factors, including, but not limited to, relative interest rates, exchange rates, monetary and fiscal policies, and trade and current account balances. The Portfolio may invest without limitation in securities denominated in foreign currencies and in U.S. dollar-denominated securities of foreign issuers. The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to within 5% (plus or minus) of the foreign currency exposure of the Bloomberg Barclays Global Aggregate (USD Hedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 0.04%. The Portfolio may invest in securities and instruments that are economically tied to emerging market countries in an amount up to 5% of its total assets above the level of those types of securities and instruments represented in the Bloomberg Barclays Global Aggregate (USD Hedged) Index. The Portfolio may also invest up to 5% of its total assets in preferred securities. In addition, the Portfolio may invest in both investment-grade securities and high yield securities (“junk bonds”) subject to a maximum of 10% of its total assets in securities rated below BBB by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The average portfolio duration of this Portfolio normally varies within 1.5 years (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays Global Aggregate (USD Hedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 7.27 years. In addition, the average U.S. portfolio duration of this Portfolio normally varies within 1 year (plus or minus) of the U.S. portfolio duration of the securities comprising the Bloomberg Barclays Global Aggregate (USD Hedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 6.11 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates or improving credit fundamentals for a particular sector or security.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Small Portfolio Risk:the risk that a smaller Portfolio may not achieve investment or trading efficiencies. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the
lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk

April 30, 2021 | PROSPECTUS  2

PIMCO Global Core Bond (Hedged) Portfolio

Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio's broad-based securities market index is the Bloomberg Barclays Global Aggregate (USD Hedged) Index. The Bloomberg Barclays Global Aggregate (USD Hedged) Index provides a broad-based measure of the global investment-grade fixed income markets hedged to U.S. dollars. The three major components of this index are the U.S. Aggregate, the Pan-European Aggregate, and the Asian-Pacific Aggregate Indices. The index also includes Eurodollar and Euro-Yen corporate bonds, Canadian Government securities, and USD investment grade 144A securities. It is not possible to invest directly in an unmanaged index. 
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class (1)
Best Quarter
June 30, 2020
4.32%
Worst Quarter
March 31, 2013
-4.34%

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Administrative Class Return(1)
8.10%
5.59%
2.34%
5/2/2011
Bloomberg Barclays Global Aggregate
(USD Hedged) Index (reflects no
deductions for fees, expenses or taxes)
5.58%
4.49%
4.25%
 
1
Since the Portfolio’s Institutional Class has not commenced operations as of the date of this prospectus, the bar chart and the table show performance of the Portfolio’s Administrative Class shares, which are offered in a separate prospectus. Although the Institutional Class and Administrative Class would have substantially similar annual returns (because they represent interests in the same portfolio of securities), Institutional Class and Administrative Class performance would differ to the extent that the Institutional Class has lower expenses.
Investment Adviser/Portfolio Managers
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Balls, Sachin Gupta and Lorenzo Pagani. Mr. Balls is CIO Global Fixed Income and a Managing Director of PIMCO. Mr. Gupta and Dr. Pagani are Managing Directors of PIMCO. Mr. Balls has managed the Portfolio since October 2011, Mr. Gupta has managed the Portfolio since September 2014, and Dr. Pagani has managed the Portfolio since October 2016.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your
salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Small Portfolio Risk
A smaller Portfolio may not grow to or maintain an economically viable size to achieve investment or trading efficiencies, which may negatively impact performance and/or force the Portfolio to liquidate. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchases or redemptions.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.

April 30, 2021 | PROSPECTUS  7

PIMCO Variable Insurance Trust

In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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PIMCO Variable Insurance Trust

transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.56% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.31% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Global Core Bond (Hedged)
Andrew Balls
10/11
CIO Global Fixed Income and Managing Director, PIMCO. He joined PIMCO in 2006 and is a
member of the Investment Committee and head of European portfolio management. Prior to
joining PIMCO, he spent eight years at the Financial Times, most recently as editor of the
U.S. Lex column and as chief economics correspondent in Washington, D.C.
PIMCO Global Core Bond (Hedged)
Sachin Gupta
9/14
Managing Director, PIMCO. Mr. Gupta joined PIMCO in 2003. He has previously managed
European LDI portfolios and served on the global portfolio management team in PIMCO's
Singapore office. Mr. Gupta has focused on investments in government bonds, sovereign
credit derivatives and interest rate derivatives across developed markets. Prior to joining
PIMCO, Mr. Gupta was in the fixed income and currency derivatives group at ABN AMRO
Bank. He has investment experience since 1998 and holds an MBA from XLRI, India.
PIMCO Global Core Bond (Hedged)
Lorenzo Pagani
10/16
Managing Director, PIMCO. Dr. Pagani joined PIMCO in 2004 and is a portfolio manager in
PIMCO's Munich office and head of the European government bond and European rates
desk. Prior to joining PIMCO, he was with the nuclear engineering department at the
Massachusetts Institute of Technology and with Procter & Gamble in Italy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

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investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder

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purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.

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Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by

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the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may
participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying

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property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real
estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and

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equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign
governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.

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Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.

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Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political
subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes

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in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which
they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or

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otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant
foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but

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only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in
“Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are

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relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies
involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.

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Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled
vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no

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Prospectus

added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a
portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not

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evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents,
custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. The information below reflects financial results for Administrative Class shares of the Portfolio, which are offered in a different prospectus. Institutional Class shares of the Portfolio had not commenced operations during the periods shown. The performance shown below differs from that which would have been achieved by Institutional Class shares of the Portfolio to the extent that the Institutional Class has lower expenses than the Administrative Class. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Global Core Bond (Hedged) Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$9.93
$0.20
$0.57
$0.77
$(0.62)
$0.00
$0.00
$(0.62)
12/31/2019
9.41
0.21
0.53
0.74
(0.22)
0.00
0.00
(0.22)
12/31/2018
9.47
0.18
(0.08)
0.10
(0.16)
0.00
0.00
(0.16)
12/31/2017
9.21
0.15
0.24
0.39
(0.13)
0.00
0.00
(0.13)
12/31/2016
8.77
0.21
0.38
0.59
(0.15)
0.00
0.00
(0.15)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Effective October 21, 2016, the Portfolio’s Investment advisory fee was decreased by 0.15% to an annual rate of 0.25% and the Portfolio’s supervisory and administrative fee was decreased by 0.04% to an annual rate of 0.31%

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.08
8.10%
$92,145
0.78%
0.78%
0.71%
0.71%
1.98%
665%
9.93
7.88
97,876
0.84
0.84
0.71
0.71
2.19
375
9.41
1.05
110,302
0.76
0.76
0.71
0.71
1.87
327
9.47
4.29
107,869
0.76
0.76
0.71
0.71
1.61
292
9.21
6.78
107,052
0.91(d)
0.91(d)
0.86(d)
0.86(d)
2.31
342

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2004F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
STRATEGIC ASSET ALLOCATION PORTFOLIO WITH DYNAMIC RISK MANAGEMENT
PIMCO Global Diversified Allocation Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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1
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A-1


PIMCO Global Diversified Allocation Portfolio

Investment Objective
The Portfolio seeks to maximize risk-adjusted total return relative to a blend of 60% MSCI World Index/40% Bloomberg Barclays U.S. Aggregate Index.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.85%
Distribution and/or Service (12b-1) Fees
0.15%
Acquired Fund Fees and Expenses(1)
0.57%
Total Annual Portfolio Operating Expenses(2)
1.57%
Fee Waiver and/or Expense Reimbursement(3)
(0.53%)
Total Annual Portfolio Operating Expenses After Fee Waiver
and/or Expense Reimbursement
1.04%
1
Acquired Fund Fees and Expenses include interest expense of the Underlying PIMCO Funds of 0.04%. Interest expense can result from certain transactions within the Underlying PIMCO Funds and is separate from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense of the Underlying PIMCO Funds, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 1.00% for Administrative Class shares.
2
Total Annual Portfolio Operating Expenses do not match the Ratio of Expenses to Average Net Assets Excluding Waivers of the Portfolio, as set forth in the Financial Highlights table of the Portfolio’s prospectus, because the Ratio of Expenses to Average Net Assets Excluding Waivers reflects the operating expenses of the Portfolio and does not include Acquired Fund Fees and Expenses.
3
PIMCO has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the expenses attributable to the Management Fees of Underlying PIMCO Funds indirectly incurred by the Portfolio in connection with its investments in Underlying PIMCO Funds, to the extent the Portfolio’s Management Fees are greater than or equal to the Management Fees of the Underlying PIMCO Funds. This waiver renews annually for a full year unless terminated by PIMCO upon at least 30 days' notice prior to the end of the contract term. For purposes of the expense reduction described above, references to Underlying PIMCO Funds include funds of PIMCO ETF Trust.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these
assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$106
$444
$805
$1,822
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 23% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing in a combination of Acquired Funds and/or direct investments and utilizing hedging techniques to manage downside risks and total portfolio volatility. The Portfolio will invest under normal circumstances in a combination of affiliated funds registered under the Investment Company Act of 1940, as amended (the “1940 Act”), equity securities, Fixed Income Instruments, forwards and derivatives. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio may invest in Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end investment companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management (“Underlying PIMCO Funds”), and may also invest in other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds, which may or may not be registered under the 1940 Act (collectively, “Acquired Funds”). The Portfolio will invest in Acquired Funds, securities, instruments and other investments to the extent permitted under the 1940 Act, or any exemptive relief therefrom. To the extent the Portfolio invests in Underlying PIMCO Funds, PIMCO expects to select such Underlying PIMCO Funds without considering or canvassing the universe of available unaffiliated Acquired Funds. The Portfolio will invest either directly or indirectly (through a fund) in instruments that are economically tied to at least three countries (one of which may be the United States).
The Portfolio’s investments will be utilized, in part, in seeking to limit the Portfolio’s overall volatility. Volatility is a measure of the magnitude of up and down fluctuations in the value of a financial instrument over time and typically results from rapid price swings. Under normal conditions, the Portfolio will seek to target an annualized volatility level of approximately 10%. A higher volatility level indicates more frequent or rapid up and down fluctuations in the value of the Portfolio relative to a lower volatility level. For example, in a more volatile market environment, PIMCO may decrease long derivative positions in volatile assets or assume a short position through derivatives in such assets in an attempt to potentially reduce the Portfolio’s volatility. The Portfolio’s

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

transactions used to target volatility are generally determined by proprietary quantitative models that take into consideration factors that may include asset class volatilities and correlations. The proprietary quantitative models are developed and maintained by PIMCO, and are subject to change over time without notice in PIMCO’s discretion. PIMCO retains discretion to override a model’s recommendation. PIMCO’s use of Acquired Funds and direct investments in seeking to manage volatility will be consistent with the Portfolio’s target asset allocation guidelines described below. There can be no assurance that investment decisions made in seeking to manage Portfolio volatility will achieve the desired results.
On average, the Portfolio will target approximately 60% equity-related exposure and 40% Fixed Income Instruments-related exposure; however, the Portfolio may adjust its overall equity exposure in seeking to manage the Portfolio’s overall volatility. The Portfolio will normally limit its equity-related exposure to 15% to 80% of its total assets. The Portfolio will typically seek to gain equity-related exposure by investing (directly or indirectly through Acquired Funds) in derivatives, including, but not limited to, options, futures contracts or swap agreements, common stock, preferred securities and equity securities of real estate investment trusts. With respect to its direct or indirect (through a fund) investments in equity securities, there is no limitation on the market capitalization range of the issuers in which the Portfolio may invest. The Portfolio may invest up to 10% of its total assets in commodity-related investments (including investment in commodity-related Underlying PIMCO Funds). The Portfolio may invest, without limitation, in securities denominated in foreign currencies and in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 25% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest in such instruments without limitation subject to any applicable legal or regulatory limitation). In addition, the Portfolio may invest in both investment-grade securities and high yield securities (“junk bonds”), subject to a maximum of 10% of its total assets in securities rated below B by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may purchase and sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales.
As part of its investment process, PIMCO will seek to reduce exposure to certain downside risks by implementing various hedging transactions. These hedging transactions seek to reduce the Portfolio’s exposure to certain severe, unanticipated market events that could significantly detract from returns. The Portfolio’s hedging transactions are generally determined by a systematic process that seeks to maintain hedge efficacy while reducing the long-term cost of hedging. PIMCO retains discretion to override the output of the systematic process.
Additional information for the Underlying PIMCO Funds can be found in the Statement of Additional Information and/or the Underlying PIMCO Funds’ prospectuses and financial reports. Additional Underlying PIMCO Funds may be added or deleted in the future without shareholder notification.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio include risks from direct investments and/ or indirect exposure through investment in Acquired Funds. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are:
Allocation Risk:the risk that a Portfolio could lose money as a result of less than optimal or poor asset allocation decisions. The Portfolio could miss attractive investment opportunities by underweighting markets that subsequently experience significant returns and could lose value by overweighting markets that subsequently experience significant declines
Acquired Fund Risk:the risk that a Portfolio's performance is closely related to the risks associated with the securities and other investments held by the Acquired Funds and that the ability of a Portfolio to achieve its investment objective will depend upon the ability of the Acquired Funds to achieve their investment objectives
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield

April 30, 2021 | PROSPECTUS  2

PIMCO Global Diversified Allocation Portfolio

securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Model Risk:the risk that the Portfolio’s investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in the Portfolio
Commodity Risk:the risk that investing in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought,
floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Real Estate Risk:the risk that the Portfolio’s investments in Real Estate Investment Trusts (“REITs”) or real estate-linked derivative instruments will subject the Portfolio to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. A Portfolio’s investments in REITs or real estate-linked derivative instruments subject it to management and tax risks. In addition, privately traded REITs subject a Portfolio to liquidity and valuation risk
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Smaller Company Risk:the risk that the value of securities issued by a smaller company may go up or down, sometimes rapidly and

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

unpredictably as compared to more widely held securities, due to narrow markets and limited resources of smaller companies. A Portfolio’s investments in smaller companies subject it to greater levels of credit, market and issuer risk
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO, including the use of quantitative models or methods, will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Tax Risk:the risk that the tax treatment of swap agreements and other derivative instruments, such as commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures, may be affected by future regulatory or legislative changes that could affect whether income from such investments is “qualifying income” under Subchapter M of the Internal Revenue Code, or otherwise affect the character, timing and/or amount of the Portfolio’s taxable income or gains and distributions
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Value Investing Risk:a value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
Exchange-Traded Fund Risk:the risk that an exchange-traded fund may not track the performance of the index it is designed to track, among other reasons, because of exchange rules, market prices of shares of an exchange-traded fund may fluctuate rapidly and materially, or shares of an exchange-traded fund may trade significantly above or below net asset value, any of which may cause losses to the Portfolio invested in the exchange-traded fund
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that
currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The 60% MSCI World Index/40% Bloomberg Barclays U.S. Aggregate Index is a blended index. The MSCI World Index is a free float-adjusted market capitalization weighted index that is designed to measure the equity market performance of developed markets. The MSCI World Index consists of 23 developed market country indices. The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable, and dollar denominated. The Bloomberg Barclays U.S. Aggregate Index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.

April 30, 2021 | PROSPECTUS  4

PIMCO Global Diversified Allocation Portfolio

Calendar Year Total Returns — Administrative Class
Best Quarter
March 31, 2019
9.84%
Worst Quarter
March 31, 2020
-12.61%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Administrative Class Return
4.15%
7.78%
5.88%
4/30/2012
60% MSCI World Index/40%
Bloomberg Barclays U.S. Aggregate
Index (reflects no deductions for fees,
expenses or taxes)
13.31%
9.34%
8.10%
 
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Graham Rennison and Yang Lu. Mr. Rennison is a Senior Vice President of PIMCO, and he has managed the Portfolio since December 2015. Mr. Lu is a Vice President of PIMCO, and he has managed the Portfolio since April 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

5  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
As the Portfolio may invest in shares of Acquired Funds, including the Underlying PIMCO Funds, the risks of investing in the Portfolio may be closely related to the risks associated with the Acquired Funds, including Underlying PIMCO Funds, and their investments. However, as the Portfolio may also invest its assets directly in stocks or bonds of other issuers and in other instruments, such as forwards, options, futures contracts or swap agreements, the Portfolio may be directly exposed to certain risks described below. As such, unless stated otherwise, any reference in this section to “Portfolios” includes both the Portfolio and Acquired Funds. Where necessary in this section, the Portfolio is specifically referred to as the “Portfolio.”
Allocation Risk
The Portfolio’s investment performance depends upon how its assets are allocated and reallocated according to the Portfolio’s asset allocation targets and ranges. A principal risk of investing in the Portfolio is that PIMCO will make less than optimal or poor asset allocation decisions. PIMCO attempts to identify investment allocations that will provide consistent, quality performance for the Portfolio, but there is no guarantee that such allocation techniques will produce the desired results. It is possible that PIMCO will focus on an investment that performs poorly or underperforms other investments under various market conditions. You could lose money on your investment in the Portfolio as a result of these allocation decisions.
Acquired Fund Risk
Because the Portfolio may invest its assets in Acquired Funds, the risks associated with investing in the Portfolio may be closely related to the risks associated with the securities and other investments held by the Acquired Funds. The ability of the Portfolio to achieve its investment objective may depend upon the ability of the Acquired Funds to achieve their respective investment objectives. There can be no assurance that the investment objective of any Acquired Fund will be achieved.
The Portfolio’s net asset value (“NAV”) will fluctuate in response to changes in the NAVs of the Acquired Funds in which it invests. The extent to which the investment performance and risks associated with the Portfolio correlates to those of a particular Acquired Fund will depend upon the extent to which the Portfolio’s assets are allocated from time to time for investment in the Acquired Fund, which may vary. As discussed under “Description of Principal Risks—Market Risk,” because the NAV of the Portfolio is related to the NAVs of the Acquired Funds in which it invests, inaccuracies, delays or other disruptions in the calculation of an Acquired Fund’s NAV may adversely impact the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the NAV of the Portfolio’s shares.

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A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the

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Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio and certain Acquired Funds may rely on various third-party sources to calculate their respective NAVs. As a result, the Portfolio and such Acquired Funds are subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s and Acquired Funds' calculations of their NAVs, and such NAV calculation issues may result in inaccurately calculated NAVs, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. Also, because the NAV of the Portfolio is related to the NAVs of the Acquired Funds in which it invests, the Portfolio may be adversely impacted by such inaccuracies, delays or other disruptions in the calculation of an Acquired Fund's NAV. The Portfolio may be unable to recover any losses associated with such failures.

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Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the

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Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests. These factors include the possibility that the Portfolio's commodity derivatives positions, may have different roll dates, reset dates or contract months than those specified in a particular commodity index.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Model Risk
In making investment allocation decisions for a Portfolio or certain Underlying PIMCO Funds, as applicable, PIMCO or the Sub-Adviser, as applicable, may utilize quantitative models that may be proprietary or developed by third-parties. These models are used by PIMCO or the Sub-Adviser, as applicable, to determine (or assist in determining) the Portfolio’s or Underlying PIMCO Fund’s target asset allocation and to identify potentially attractive relative value and risk hedging strategies. The investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in a Portfolio or Underlying PIMCO Fund. There can be no assurance that the models used by PIMCO or the Sub-Adviser, as applicable, will remain viable, due to various factors, which may include the quality of the data input into the models and the

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assumptions underlying such models, which to varying degrees involve the exercise of judgment, as well as the possibility of errors in constructing or using the model. In addition, in constructing the underlying index of, or model portfolio for, an Underlying PIMCO Fund that seeks to track the investment results of such underlying index or model portfolio, the index provider or sub-adviser, as applicable, may utilize quantitative models or methodologies that may be proprietary or developed by third-parties. These models and methodologies are used to help determine the composition of the underlying index or model portfolio and may not adequately take into account certain factors, resulting in a decline in the value of the underlying index or model portfolio and, therefore, the Underlying PIMCO Fund.
Models rely on accurate market data inputs. If inaccurate market data is entered into a model, the resulting information will be incorrect. In addition, the models used may be predictive in nature and such models may result in an incorrect assessment of future events. The models evaluate securities or securities markets based on certain assumptions concerning the interplay of market factors. The markets or the prices of individual securities may be affected by factors not foreseen in developing the models. In addition, when relying on a quantitative model and/or data supplied by third parties, PIMCO or the Sub-Adviser may have less insight into the construction, coding or testing of the third-party model or data, and PIMCO and the Sub-Adviser will be exposed to systems, cyber security and other risks associated with the third party that provides the model or data.
The use of models can be complex and involves financial, economic, econometric and statistical theories, research and modeling; and the results of those processes must then be translated into computer code. Although PIMCO and the Sub-Adviser seek to hire individuals and/or third parties, as applicable, skilled in each of these functions and to provide appropriate levels of oversight, the complexity of the individual tasks, the difficulty of integrating such tasks, and the limited ability to perform “real world” testing of a model’s end product raises the chances that a finished model may contain an error; one or more of such errors could adversely affect a Portfolio’s or an Underlying PIMCO Fund’s performance.
Commodity Risk
The Portfolio’s investments in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments. Certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, may each concentrate its assets in a particular sector of the commodities market (such as oil, metal or agricultural products). As a result, certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, and, to the extent the Portfolio invests in certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund or PIMCO CommodityRealReturn Strategy Fund®, the Portfolio may be more susceptible to risks associated with those sectors. The prices for commodities in those sectors may fluctuate widely due to factors such as changes in value, supply and demand and governmental regulatory policies.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other

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asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invest exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Real Estate Risk
Investments in real estate investment trusts (“REITs”) or real estate-linked derivative instruments are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. An investment in a REIT or a real estate-linked derivative instrument that is linked to the value of a REIT is subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (the “Code”). In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. Finally, private REITs are not traded on a national securities exchange. As such, these products are generally illiquid. This reduces the ability of a Portfolio to redeem its investment early. Private REITs are also generally harder to value and may bear higher fees than public REITs.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In

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such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities (or the value of the Acquired Funds). Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.

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PIMCO Variable Insurance Trust

Smaller Company Risk
The general risks associated with fixed income securities and equity securities are particularly pronounced for securities issued by companies with smaller market capitalizations. These companies may have limited product lines, markets or financial resources or they may depend on a few key employees. As a result, they may be subject to greater levels of credit, market and issuer risk. Securities of smaller companies may trade less frequently and in lesser volumes than more widely held securities and their values may fluctuate more sharply than other securities. Companies with medium-sized market capitalizations may have risks similar to those of smaller companies.
Management Risk
The Portfolio and certain Acquired Funds are subject to management risk because they are actively managed investment portfolios. PIMCO, or in the case of a fund that is not managed by PIMCO, such other fund’s investment adviser and sub-adviser, as applicable, and each individual portfolio manager will apply investment techniques and risk analysis and will, in some cases, rely partially or entirely upon or be informed by one or more quantitative models in making investment decisions for the Portfolio and the Acquired Funds, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio or an Acquired Fund seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio or Acquired Fund. To the extent the Portfolio or Acquired Fund employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio or Acquired Fund. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Because a number of Underlying PIMCO Funds obtain exposure to certain proprietary model stock portfolios by investing in equity total return swaps based on such model portfolios, in other securities and instruments to replicate the performance of such model portfolios, or directly in the equity securities held in such model portfolios, such Underlying PIMCO Funds will be subject to the risks associated with the management of these proprietary model stock portfolios by the Sub-Adviser to such Underlying PIMCO Funds. Similarly, there can be no assurance that quantitative models or methods utilized by PIMCO or the Sub-Adviser or related data sources will always be available, and the loss of access to any such model(s) or data sources could have an adverse impact on the Underlying PIMCO Fund’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Risk
The PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds, gain exposure to the commodities markets through investments in commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures. Each of the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund may also gain exposure indirectly to commodity markets by investing in its respective subsidiary (each a “Subsidiary” and collectively, the “Subsidiaries”), which invests primarily in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and/or other Fixed Income Instruments. In order for the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”), each Underlying PIMCO Fund must derive at least 90 percent of its gross income each taxable year from certain qualifying sources of income.
As more fully described below under “Tax Consequences-A Note on the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds”, the Internal Revenue Service (the “IRS”) issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. The IRS has issued private letter rulings in which the IRS specifically concluded that income derived from an investment in a subsidiary will also constitute qualifying income. Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if an Underlying PIMCO Fund‘s income from an investment in the subsidiary is distributed annually or is derived with respect to the Underlying PIMCO Fund’s business of investing in securities. An IRS revenue procedure states that the IRS will not issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the Investment Company Act of 1940, as amended (the “1940 Act”).
The PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund will seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in their respective Subsidiaries. If the IRS were to determine that income derived from certain commodity-linked notes or from investments in a Subsidiary does not constitute qualifying income, certain Underlying PIMCO Funds, including the PIMCO CommodityRealReturn Strategy Fund and PIMCO CommoditiesPLUS® Strategy Fund, might be adversely affected and would be required to reduce their exposure to such investments which might result in difficulty in implementing their investment strategies and increased costs and taxes. The use of commodity index-linked notes and investments in a Subsidiary involve specific risks. See “Characteristics and Risks of Securities and Investment Techniques—Derivatives—A Note on the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds” below for further information regarding commodity index-linked notes, including the risks associated with these instruments. In addition, see “Characteristics and Risks of Securities and Investment Techniques-Investments in a Wholly-Owned Subsidiary” below for further information regarding the Subsidiaries, including the risks associated with investing in the Subsidiaries.
To the extent the Portfolio invests in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund®, or PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, the use of the above noted investments by the Underlying PIMCO Fund could subject the shareholders of the Portfolio to risks similar to those borne by shareholders of the PIMCO CommodityRealReturn® Strategy and PIMCO Global Managed Asset Allocation Portfolios. See “Tax Consequences.”
Value Investing Risk
Value investing attempts to identify companies that are believed to be undervalued. Value stocks typically have prices that are low relative to factors such as the company’s earnings, cash flow or dividends. A value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur. A value investing style may perform better or worse than equity portfolios that focus on growth stocks or that have a broader investment style.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.

April 30, 2021 | PROSPECTUS  15

PIMCO Variable Insurance Trust

Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
Exchange-Traded Fund (“ETF”) Risk
Investments in ETFs entail certain risks. Investments in ETFs designed to track an index involve the risk that the ETF’s performance may not track the performance of the index the ETF is designed to track. This deviation may occur due to cash inflows and outflows from and to investors buying and redeeming shares or due to occasional differences between the composition of the index and the securities held by the ETF. In addition, investments in ETFs involve the risk that the market prices of ETF shares will fluctuate, sometimes rapidly and materially, in response to changes in the ETF’s NAV, the value of ETF holdings and supply and demand for ETF shares. Although ETFs will generally trade close to NAV, market volatility, lack of an active trading market for ETF shares, disruptions at market participants (such as Authorized Participants or market makers) and any disruptions in the ordinary functioning of the creation/redemption process may result in ETF shares trading significantly above (at a “premium”) or below (at a “discount”) NAV. Significant losses may result when transacting in ETF shares in these and other circumstances.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

16  Prospectus | PIMCO Variable Insurance Trust

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.85% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.45% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.40% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Fund of Funds Fees
The Portfolio is permitted to invest in Underlying PIMCO Funds, which, for the Portfolio, is defined to include Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end investment companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. The Portfolio is further permitted to invest in Acquired Funds, which, for the Portfolio, is defined to include the Underlying PIMCO Funds and other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds, which may or may not be registered under the 1940 Act.
The Portfolio pays advisory and supervisory and administrative fees directly to PIMCO at an annual rate stated above, based on the average daily net assets attributable in the aggregate to the Portfolio’s Administrative Class shares. The Portfolio also indirectly pays its proportionate share of the advisory, supervisory and administrative and management fees charged by PIMCO to the Underlying PIMCO Funds and, to the extent not included among the Underlying PIMCO Funds, funds of PIMCO ETF Trust in which the Portfolio invests (collectively, “Underlying PIMCO Fund Fees”).
PIMCO has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, to the extent necessary, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the Underlying PIMCO Fund Fees indirectly incurred by the Portfolio in connection with its investments in Underlying PIMCO Funds (for purposes of this expense reduction, this term includes funds of PIMCO ETF Trust), to the extent the Portfolio's advisory fee or advisory fee and supervisory and administrative fee, taken together, are greater than or equal to the Underlying PIMCO Fund Fees. This waiver will automally renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the current term.
The Acquired Fund Fees and Expenses shown in the Annual Portfolio Operating Expenses table for the Portfolio may be higher than the Underlying PIMCO Fund Fees used for purposes of the Expense Reduction shown in that table due to differences in the methods of calculation. The Acquired Fund Fees and Expenses, as required to be shown in the Annual Portfolio Operating Expenses table, are calculated using the total operating expenses for each Underlying PIMCO Fund (or any unaffiliated funds) over the Portfolio’s average net assets. The Underlying PIMCO Fund Fees that are used for purposes of implementing the expense reduction described above are calculated using the advisory and supervisory and administrative fees for each Underlying PIMCO Fund (and any unaffiliated funds) over the total assets invested in Underlying PIMCO Funds. Thus, the Acquired Fund Fees and Expenses listed in the Annual Portfolio Operating Expenses table will typically be higher than the Underlying PIMCO Fund Fees used to calculate the Expense Reduction when the Portfolio employs leverage as an investment strategy.
The expenses associated with investing in a fund of funds are generally higher than those for mutual funds that do not invest in other funds. The cost of investing in the Portfolio will generally be higher than the cost of investing in a portfolio that invests directly in individual stocks and bonds. By investing in the Portfolio, an investor will indirectly bear fees and expenses charged by non-PIMCO Acquired Funds (and may indirectly bear a portion of the fees and expenses charged by Underlying PIMCO Funds, to the extent such fees and expenses are not waived or reimbursed pursuant to applicable waiver and reimbursement agreements), in addition to the Portfolio’s direct fees and expenses. In addition, the use of a fund of funds structure could affect the timing, amount and character of distributions to shareholders and may therefore increase the amount of taxes payable by shareholders. The Portfolio invests, to the extent it invests in Underlying PIMCO Funds, invests in Institutional Class or Class M shares of the Underlying PIMCO Funds, which are not subject to any sales charges or distribution (12b-1) fees.
The following table summarizes the annual expenses borne by Institutional Class or Class M shareholders of the Underlying PIMCO Funds. Because the Portfolio, to the extent it invests in Underlying PIMCO Funds, invests in Institutional Class or Class M shares of the Underlying PIMCO Funds, shareholders of the Portfolio would indirectly bear a proportionate share of these expenses, depending upon how the Portfolio’s assets are allocated from time to time among the Underlying PIMCO Funds.
For a complete description of an Underlying PIMCO Fund, please see the Underlying PIMCO Fund’s prospectus or offering memorandum, as applicable. For a summary description of the Underlying PIMCO Funds, please see the “Descriptions of the Underlying PIMCO Funds” section in this prospectus.
Annual Underlying PIMCO Fund Expenses
(Based on the average daily net assets attributable to an Underlying PIMCO Fund’s Institutional Class shares (or Class M shares in the case of the PIMCO Government Money Market Fund )).
Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO California Intermediate Municipal Bond Fund
0.445%
0.00%
0.445%
PIMCO California Municipal Bond Fund
0.44%
0.02%
0.46%
PIMCO California Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Climate Bond Fund
0.50%
0.00%
0.50%
PIMCO CommoditiesPLUS® Strategy Fund
0.74%
0.27%
1.01%(3)
PIMCO CommodityRealReturn Strategy Fund®
0.74%
0.76%
1.50%(4)

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PIMCO Variable Insurance Trust

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO Credit Opportunities Bond Fund
0.90%
0.02%
0.92%
PIMCO Diversified Income Fund
0.75%
0.04%
0.79%
PIMCO Dividend and Income Fund
0.75%
0.05%
0.80%(5)
PIMCO Dynamic Bond Fund
0.80%
0.05%
0.85%
PIMCO Emerging Markets Bond Fund
0.83%
0.05%
0.88%
PIMCO Emerging Markets Corporate Bond Fund
0.90%
0.12%
1.02%
PIMCO Emerging Markets Currency and Short-Term Investments Fund
0.85%
0.03%
0.88%
PIMCO Emerging Markets Local Currency and Bond Fund
0.90%
0.80%
1.70%
PIMCO ESG Income Fund
0.50%
0.07%
0.57%(6)
PIMCO Extended Duration Fund
0.50%
1.21%
1.71%
PIMCO Global Advantage® Strategy Bond Fund
0.65%
0.21%
0.86%
PIMCO Global Bond Opportunities Fund (U.S. Dollar-Hedged)
0.55%
0.04%
0.59%
PIMCO Global Bond Opportunities Fund (Unhedged)
0.55%
0.12%
0.67%
PIMCO GNMA and Government Securities Fund
0.50%
0.33%
0.83%
PIMCO Government Money Market Fund
0.18%
0.00%
0.18%(7)
PIMCO High Yield Fund
0.55%
0.02%
0.57%
PIMCO High Yield Municipal Bond Fund
0.55%
0.08%
0.63%
PIMCO High Yield Spectrum Fund
0.60%
0.02%
0.62%
PIMCO Income Fund
0.50%
0.59%
1.09%
PIMCO International Bond Fund (U.S. Dollar-Hedged)
0.50%
0.10%
0.60%
PIMCO International Bond Fund (Unhedged)
0.50%
0.13%
0.63%
PIMCO Investment Grade Credit Bond Fund
0.50%
0.35%
0.85%
PIMCO Long Duration Total Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term Credit Bond Fund
0.55%
0.29%
0.84%
PIMCO Long-Term Real Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term U.S. Government Fund
0.475%
1.38%
1.855%
PIMCO Low Duration Credit Fund(8)
0.70%
0.05%
0.75%
PIMCO Low Duration ESG Fund
0.50%
0.08%
0.58%
PIMCO Low Duration Fund
0.46%
0.41%
0.87%
PIMCO Low Duration Fund II
0.50%
0.03%
0.53%
PIMCO Low Duration Income Fund
0.50%
0.05%
0.55%
PIMCO Moderate Duration Fund
0.46%
0.15%
0.61%
PIMCO Mortgage Opportunities and Bond Fund
0.60%
1.22%
1.82%
PIMCO Mortgage-Backed Securities Fund
0.50%
0.25%
0.75%
PIMCO Municipal Bond Fund
0.44%
0.07%
0.51%
PIMCO National Intermediate Municipal Bond Fund
0.45%
0.00%
0.45%
PIMCO New York Municipal Bond Fund
0.445%
0.05%
0.495%
PIMCO Preferred and Capital Securities Fund
0.79%
0.09%
0.88%(9)
PIMCO RAE Emerging Markets Fund
0.75%
0.02%
0.77%(10)
PIMCO RAE Fundamental Advantage PLUS Fund
0.89%
0.07%
0.96%
PIMCO RAE International Fund
0.50%
0.02%
0.52%(5)
PIMCO RAE PLUS EMG Fund
1.10%
0.21%
1.31%
PIMCO RAE PLUS Fund
0.79%
0.08%
0.87%
PIMCO RAE PLUS International Fund
0.82%
0.05%
0.87%
PIMCO RAE PLUS Small Fund
0.84%
0.09%
0.93%
PIMCO RAE US Fund
0.40%
0.02%
0.42%(5)
PIMCO RAE US Small Fund
0.50%
0.04%
0.54%
PIMCO RAE Worldwide Long/Short PLUS Fund
1.19%
0.09%
1.28%
PIMCO Real Return Fund
0.45%
0.08%
0.53%
PIMCO RealEstateRealReturn Strategy Fund
0.74%
1.36%
2.10%
PIMCO Short Asset Investment Fund
0.34%
0.02%
0.36%
PIMCO Short Duration Municipal Income Fund
0.33%
0.00%
0.33%

20  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO Short-Term Fund
0.45%
0.10%
0.55%
PIMCO StocksPLUS® Absolute Return Fund
0.64%
0.08%
0.72%
PIMCO StocksPLUS® Fund
0.50%
0.06%
0.56%
PIMCO StocksPLUS® International Fund (U.S. Dollar-Hedged)
0.75%
0.25%
1.00%
PIMCO StocksPLUS® International Fund (Unhedged)
0.64%
0.38%
1.02%
PIMCO StocksPLUS® Long Duration Fund
0.59%
0.42%
1.01%
PIMCO StocksPLUS® Short Fund
0.64%
0.45%
1.09%
PIMCO StocksPLUS® Small Fund
0.69%
0.06%
0.75%
PIMCO Strategic Bond Fund
0.55%
0.02%
0.57%(11)
PIMCO Total Return ESG Fund
0.50%
0.46%
0.96%
PIMCO Total Return Fund
0.46%
0.24%
0.70%
PIMCO Total Return Fund II
0.50%
0.26%
0.76%
PIMCO Total Return Fund IV
0.50%
0.30%
0.80%
PIMCO TRENDS Managed Futures Strategy Fund
1.40%
0.29%
1.69%(12)
1
“Management Fees” reflects an advisory fee and a supervisory and administrative fee payable by an Underlying PIMCO Fund to PIMCO.
2
Other Expenses include expenses such as organizational expenses, interest expense, taxes, governmental fees, pro rata Trustees' fees and acquired fund fees and expenses attributable to the Institutional Class or Class M shares or the Fund in the case of exchange-traded funds of the PIMCO ETF Trust or PIMCO Equity Series.
3
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund III Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
4
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund I Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
5
PIMCO has contractually agreed, through October 31, 2021, to waive a portion of the Fund's supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund's organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Equity Series at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
6
PIMCO has contractually agreed, through July 31, 2022, to waive a portion of the Fund’s supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
7
To maintain certain net yields for the Fund, PIMCO or its affiliates may temporarily and voluntarily waive, reduce or reimburse all or any portion of the Fund's fees and expenses.
8
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund.
9
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Capital Securities Fund (Cayman) Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
10
PIMCO has contractually agreed, through July 31, 2022, to reduce its supervisory and administrative fee for each share class of the Fund by 0.05% of the average daily net assets attributable to the applicable class of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years from the date of waiver.
11
PIMCO has contractually agreed, through July 31, 2022, to reduce its advisory fee by 0.10% of the average daily net assets of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years.
12
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund VIII, Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.

April 30, 2021 | PROSPECTUS  21

PIMCO Variable Insurance Trust

Individual Portfolio Managers
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Global Diversified Allocation
Yang Lu
4/19
Vice President, PIMCO. Mr. Lu is a portfolio manager on the quantitative portfolio
management team in the Newport Beach office. Prior to joining PIMCO in 2018, he was an
analyst at Hutchin Hill Capital, responsible for developing and managing quant equity
market neutral strategies. He has investment experience since 2014 and holds an
undergraduate degree in mathematics and economics from Williams College.
PIMCO Global Diversified Allocation
Graham A. Rennison
12/15
Senior Vice President, PIMCO. Mr. Rennison is a member of the quantitative portfolio
management group, focusing on multi-asset class systematic strategies. Prior to joining
PIMCO in 2011, Mr. Rennison was associated with Barclays Capital and Lehman Brothers,
researching and publishing widely on quantitative strategies in the credit markets.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

22  Prospectus | PIMCO Variable Insurance Trust

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PIMCO Variable Insurance Trust

Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the 1940 Act, an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

24  Prospectus | PIMCO Variable Insurance Trust

Prospectus

conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

April 30, 2021 | PROSPECTUS  25

PIMCO Variable Insurance Trust

fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

26  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.The Portfolio may invest in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund. One of the requirements for favorable tax treatment as a regulated investment company under the Code is that each Underlying PIMCO Fund derive at least 90% of its gross income from certain qualifying sources of income. The IRS has issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. As such, each Underlying PIMCO Fund’s ability to utilize commodity-linked swaps as part of its

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investment strategy is limited to a maximum of 10 percent of its gross income.
However, in a subsequent revenue ruling, the IRS provides that income from alternative investment instruments (such as certain commodity index-linked notes) that create commodity exposure may be considered qualifying income under the Code. The IRS has also issued a private letter ruling to the Underlying PIMCO Funds in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued another private letter ruling to each Underlying PIMCO Fund in which the IRS specifically concluded that income derived from the Underlying PIMCO Fund’s investment in its Subsidiary will also constitute qualifying income to the Underlying PIMCO Fund, even if the Subsidiary itself owns commodity linked swaps. Each Underlying PIMCO Fund will continue to seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in its Subsidiary.
Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if an Underlying PIMCO Fund‘s income from an investment in the subsidiary is derived with respect to the Underlying PIMCO Fund’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the 1940 Act. In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings. There can be no assurance that the IRS will not change its position with respect to some or all of these conclusions or that future legislation will not adversely impact the tax treatment of each Underlying PIMCO Fund’s commodity-linked investments. If the IRS were to change or reverse its position, or if future legislation adversely affected the tax treatment of the commodity-linked investments of each Underlying PIMCO Fund, there would likely be a significant adverse impact on the Underlying PIMCO Fund, including the possibility of failing to qualify as a regulated investment company. If an Underlying PIMCO Fund did not qualify as a regulated investment company for any taxable year, its taxable income would be subject to tax at the Underlying PIMCO Fund level at regular corporate tax rates (without reduction for distributions to shareholders) and to a further tax at the shareholder level when such income is distributed.
Furthermore, the tax treatment of commodity-linked notes, other commodity-linked derivatives, and an Underlying PIMCO Fund’s investments in its Subsidiary may otherwise be adversely affected by future legislation, court decisions, Treasury Regulations and/or guidance issued by the IRS. Such developments could affect the character, timing and/or amount of the Underlying PIMCO Fund’s taxable income or any distributions made by the Underlying PIMCO Fund or result in the inability of the Underlying PIMCO Fund to operate as described in its prospectus.
A Note on the PIMCO CommodityRealReturn Strategy Fund®, an Underlying PIMCO Fund.Periodic adjustments for inflation to the principal amount of an inflation-indexed bond
may give rise to original issue discount, which will be includable in the Underlying PIMCO Fund’s gross income. Due to original issue discount, the Underlying PIMCO Fund may be required to make annual distributions to shareholders that exceed the cash received, which may cause the Underlying PIMCO Fund to liquidate certain investments when it is not advantageous to do so. Also, if the principal value of an inflation-indexed bond is adjusted downward due to deflation, amounts previously distributed in the taxable year may be characterized in some circumstances as a return of capital.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
As the Portfolio may invest in shares of the Acquired Funds, the risks of investing in the Portfolio may be closely related to the risks associated with the Acquired Funds and their investments. However, as the Portfolio may also invest its assets directly in Fixed Income Instruments, equity securities, forwards or derivatives, such as options, futures contracts or swap agreements, other affiliated or unaffiliated funds, and other investments, the Portfolio may be directly exposed to certain risks described below.
This section provides additional information about some of the principal investments and related risks of the Portfolio and of certain Acquired Funds described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio and certain Acquired Funds from time to time. Generally, the characteristics and risks of securities and investment techniques that may be used by the Acquired Funds from time to time are similar to those described below. However, the risks associated with an Acquired Fund’s investments are described more fully in each Acquired Fund’s prospectus. Accordingly, please see an Acquired Fund’s prospectus for a more complete description of the Acquired Fund and the risks associated with its investments.
Most of these securities and investment techniques described herein are discretionary, which means that PIMCO, or in the case of a fund that is not managed by PIMCO, such fund’s investment adviser and sub-adviser, as applicable, can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio or Acquired Funds. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.

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Investors should be aware that the investments made by a Portfolio and the results achieved by a Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to a Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact a Portfolio’s portfolio management. For example, a Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause Portfolios to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase a Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause a Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect a Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for an Underlying PIMCO Fund, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Underlying PIMCO Fund’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;

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repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported
by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing

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out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond
the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of

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the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower
characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the

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current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that
are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a

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smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Volatility
Volatility measures the variability in the price of an investment over time. A higher volatility level signifies an investment’s value may fluctuate over a larger range within a short period of time, either up or down. A lower volatility level means an investment’s value is more likely to change within a narrower range, or less frequently, over time. The more volatile the portfolio holdings of the Portfolio, the less predictable the returns for the Portfolio. Higher volatility levels may indicate heightened risk of losses.
PIMCO’s use of investments in seeking to manage the Portfolio‘s volatility will be consistent with the Portfolio’s asset allocation guidelines. Although asset allocation cannot eliminate investment risk or losses, it may provide opportunities to manage a Portfolio’s volatility relative to a Portfolio’s target annualized volatility level.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The

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income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this Prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions. Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights. Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time. In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In
such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
While certain Underlying PIMCO Funds will generally invest in equity derivatives, each such Underlying PIMCO Fund may invest without limit directly in equity securities, including common stocks, preferred securities and convertible securities. In addition, the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, each an Underlying PIMCO Fund, may invest in equity securities of issuers in commodity-related industries, and the PIMCO RealEstateRealReturn Strategy Fund, an Underlying PIMCO Fund, may invest in REITs and equity securities of issuers in real estate-related industries. The Portfolio may also invest directly in equity securities. When investing directly in equity securities, the Portfolio will not be limited to only those equity securities with any particular weighting in the Portfolio’s benchmark index, if any. Generally, the Portfolio may consider investing directly in equity securities when derivatives on the underlying securities appear to be overvalued.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and

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certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and
dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the

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laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate
significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.

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Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of

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the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to
use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the

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availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
A Note on the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds. In light of relevant IRS guidance, as discussed above under “Tax Consequences-A Note on the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds,” the Underlying PIMCO Funds will seek to gain exposure to the commodity markets primarily through investments in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices, and through investments in their respective Subsidiary (as discussed below). The Underlying PIMCO Funds may also invest in commodity-linked notes with principal and/or coupon payments linked to the value of particular commodities or commodity futures contracts, or a subset of commodities and commodities futures contracts. These notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in response to changes in the underlying commodity, commodity futures contract, subset of commodities, subset of commodities futures contracts or commodity index.
These notes expose the Underlying PIMCO Funds economically to movements in commodity prices. These notes also are subject to risks, such as credit, market and interest rate risks, that in general affect the values of debt securities. In addition, these notes are often leveraged, increasing the volatility of each note’s market value relative to changes in the underlying commodity, commodity futures contract or commodity index. Therefore, at the maturity of the note, the Underlying PIMCO Fund may receive more or less principal than it originally invested. The Underlying PIMCO Funds might receive interest payments on the note that are more or less than the stated coupon interest payments.
The Underlying PIMCO Funds may also invest in other commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures. The value of a commodity-linked derivative investment generally is based upon the price movements of a physical commodity (such as energy, mineral, or agricultural products), a commodity futures contract, a subset of commodities, a subset of
commodities futures contracts or commodity index, or other economic variable based upon changes in the value of commodities or the commodities markets.
Options transactions may be effected on exchanges or in the OTC market. When OTC options are purchased, the Portfolio’s portfolio bears the risk that the counterparty that wrote the option will be unable or unwilling to perform its obligations under the option contract. Options may also be illiquid and, in such cases, the Portfolio may have difficulty closing out its position. OTC options also may include options on baskets of specific securities.
Many swap transactions are privately negotiated agreements between an Underlying PIMCO Fund and a counterparty to exchange or swap investment cash flows or assets at specified intervals in the future. The obligations may extend beyond one year. There is often no central exchange for swap transactions and therefore they can be less liquid investments than exchange-traded instruments. The Dodd-Frank Act and related regulatory developments require the clearing and exchange-trading of certain standardized OTC derivative instruments that the CFTC and SEC have defined as “swaps.” The CFTC has implemented mandatory exchange-trading and clearing requirements under the Dodd-Frank Act and the CFTC continues to approve contracts for central clearing. Uncleared swaps are subject to margin requirements that are being implemented on a phased-in basis. The investment adviser will continue to monitor these developments, particularly to the extent regulatory changes affect a Portfolio’s ability to enter into swap agreements.
As described below under “Characteristics and Risks of Securities and Investment Techniques-Investments in the Wholly-Owned Subsidiary,” each Underlying PIMCO Fund may gain exposure to commodity markets by investing in its respective Subsidiary. It is expected that the Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments.
The IRS issued a revenue ruling that limits the extent to which the Underlying PIMCO Funds may invest directly in commodity-linked swaps or certain other commodity-linked derivatives. Each Subsidiary, on the other hand, may invest in these commodity-linked derivatives generally without limitation. See “Tax Consequences-A Note on the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds” above for further information.
Investments in a Wholly Owned Subsidiary
Investments in its respective Subsidiary are expected to provide the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund with exposure to the commodity markets within the limitations of Subchapter M of the Code and recent IRS revenue rulings, as discussed above under “Tax Consequences-A Note on the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds.”

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It is expected that each Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments. Although the Underlying PIMCO Funds may enter into these commodity-linked derivative instruments directly, each Underlying PIMCO Fund will likely gain exposure to these derivative instruments indirectly by investing in its respective Subsidiary. To the extent that PIMCO believes that these commodity-linked derivative instruments are better suited to provide exposure to the commodities market than commodity index-linked notes, each Underlying PIMCO Fund’s investment in its Subsidiary will likely increase. Each Subsidiary will also invest in inflation indexed securities and/or other Fixed Income Instruments, which are intended to serve as margin or collateral for the Subsidiary’s derivatives position, common and preferred securities as well as convertible securities of issuers in commodity-related industries, collateralized debt obligations, event-linked bonds and event-linked swaps. To the extent that the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund invests in its respective Subsidiary, it may be subject to the risks associated with those derivative instruments and other securities, which are discussed elsewhere in this prospectus.
While each Subsidiary may be considered similar to an investment company, it is not registered under the 1940 Act and, unless otherwise noted in the prospectus, is not subject to all of the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund and/or each Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund and, to the extent the Portfolio invests in the PIMCO CommodityRealReturn Strategy Fund® or PIMCO CommoditiesPLUS® Strategy Fund, the Portfolio. Changes in the laws of the United States and/ or the Cayman Islands could adversely affect the performance of the Portfolio and/or a Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets

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determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in Underlying PIMCO Funds and, to the extent permitted by the 1940 Act or exemptive relief therefrom, other affiliated and unaffiliated funds, which may or may not be registered under the 1940 Act, such as open-end or closed-end management investment companies, exchange-traded funds and exchange-traded vehicles. Other unaffiliated investment companies are not required to make their shares available for purchase by the Portfolio, and there is no guarantee that such investment will be, or will continue to be available. Each Underlying PIMCO Fund may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio and each Underlying PIMCO Fund may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws.

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To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective.
Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. In addition to indirectly bearing the expenses associated with portfolio turnover of the Acquired Funds, the Portfolio will directly bear these expenses to the extent that it invests in other securities and instruments.  Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objectives of the Portfolio and certain Underlying PIMCO Funds are non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval. The investment objectives of certain Underlying PIMCO Funds are fundamental and may not be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes

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in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, sub-advisers, administrators, transfer agents, custodians, distributors and other third parties), trading
counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

April 30, 2021 | PROSPECTUS  45

PIMCO Variable Insurance Trust

Descriptions of the Underlying PIMCO Funds
The Portfolio may invest its assets in some or all of the Underlying PIMCO Funds, which, for the Portfolio, is defined to include Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end investment companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. The Portfolio is further permitted to invest in Acquired Funds, which, for the Portfolio, is defined to include the Underlying PIMCO Funds and other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds, which may or may not be registered under the 1940 Act. Because the Underlying PIMCO Funds are not offered in this prospectus, the following provides a general description of the main investments and other information about the Underlying PIMCO Funds. At the discretion of PIMCO and without shareholder approval, the Portfolio may invest in additional Underlying PIMCO Funds created in the future. For a complete description of an Underlying PIMCO Fund, please see that Fund’s Institutional Class or Class M prospectus, which is incorporated herein by reference and is available free of charge by telephoning 1-800-927-4648.
Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Short Duration
PIMCO Low Duration Income
Short maturity fixed income instruments
0 to 3 years
Max 30% of total
assets below Baa(3)
No Limitation(4)
PIMCO Short Asset Investment
Money market instruments and short maturity
fixed income instruments
≤ 1.5 years
Baa to Aaa
0%
PIMCO Short-Term
Money market instruments and short maturity
fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below Baa
0-10% of total
assets(5)
PIMCO Low Duration
Short maturity fixed income instruments
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration II
Short maturity fixed income instruments with
quality and non-U.S. issuer restrictions
1 to 3 years
A to Aaa
0%
PIMCO Low Duration ESG
Short maturity fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration Credit(6)
Diversified portfolio of fixed income
instruments
0 to 3 years
Max 10% of total
assets below Caa
0-25% of total
assets(7)
Intermediate
Duration
PIMCO Moderate Duration
Short and intermediate maturity fixed income
instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO GNMA and Government
Securities
Short and intermediate maturity
mortgage-related fixed income securities issued
by the Government National Mortgage
Association and U.S. government securities
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa
0%
PIMCO High Yield
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(8) max
20% of total assets
Caa or below
0-20% of total
assets(5)
PIMCO High Yield Spectrum
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(9)
No Limitation(10)
PIMCO Mortgage-Backed Securities
Short and intermediate maturity
mortgage-related fixed income instruments
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa(11)
0%
PIMCO Total Return
Intermediate maturity fixed income instruments
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return II
Intermediate maturity fixed income instruments
with quality and non-U.S. issuer restrictions
+/-2 years of its
benchmark
Baa to Aaa
0%
PIMCO Total Return ESG
Intermediate maturity fixed income instruments
with prohibitions on firms engaged in socially
sensitive practices
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return IV
Intermediate maturity fixed income instruments
+/-1.5 years of its
benchmark
Baa to Aaa
0-15% of total
assets(7)
PIMCO Investment Grade Credit Bond
Investment grade fixed income securities
+/-2 years of its
benchmark
Max 15% of total
assets below Baa
0-30% of total
assets(5)

46  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Long Duration
PIMCO Long Duration Total Return
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Extended Duration
Long-term maturity fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO Long-Term U.S. Government
Long-term maturity fixed income securities
≥ 8 years
A to Aaa; max 25% Aa;
max 10% A
0%
PIMCO Mortgage Opportunities and
Bond
Mortgage-related assets and fixed income
instruments
(-1) to 8 years
Max 50% of total
assets below Baa(12)
0%
PIMCO Long-Term Credit Bond
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
B to Aaa; max 20% of
total assets below Baa
0-30% of total
assets(5)
Income
PIMCO ESG Income
Broad range of fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Income
Broad range of fixed income instruments
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Preferred and Capital Securities
Capital securities and preferred securities
+/-2 years of its
benchmark
No Limitation
No Limitation(4)
Inflation-Related
PIMCO Real Return
Inflation-indexed fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO Long-Term Real Return
Inflation-indexed fixed income securities
+/-4 years of its
benchmark
B to Aaa; max 20% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO CommoditiesPLUS® Strategy
Commodity-linked derivative instruments
backed by an actively managed low volatility
portfolio of fixed income instruments
≤ 1 year
Max 10% of total
assets below Baa
0-20%(4)
PIMCO CommodityRealReturn Strategy®
Commodity-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO RealEstateRealReturn Strategy
Real estate-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
Tax Exempt
PIMCO California Short Duration
Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal and California
income tax)
≤ 3 years
Caa to Aaa; max 10%
of total assets below
Baa
0%
PIMCO California Municipal Bond
Municipal securities (exempt from federal and
California income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO Short Duration Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal income tax)
≤ 3 years
Baa to Aaa
0%
PIMCO California Intermediate Municipal
Bond
Intermediate maturity municipal securities
(exempt from federal and California income
tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO National Intermediate Municipal
Bond
Municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO New York Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal and New York
income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO High Yield Municipal Bond
Intermediate to long-term maturity high yield
municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
No Limitation
0%

April 30, 2021 | PROSPECTUS  47

PIMCO Variable Insurance Trust

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
PIMCO Emerging Markets Bond
Emerging market fixed income instruments
+/- 2 years of its
benchmark
Max 15% of total
assets below B
≥ 80% of assets(14)
PIMCO Emerging Markets Currency and
Short-Term Investments
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and short-term investments
≤ 2 years
Max 15% of total
assets below B
No Limitation(15)
PIMCO International Bond
(U.S. Dollar-Hedged)
Intermediate maturity hedged non-U.S. fixed
income instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO International Bond (Unhedged)
Intermediate maturity non-U.S. fixed income
instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation
PIMCO Global Advantage® Strategy
Bond
U.S. and non-U.S. fixed income instruments
≤ 8 years
Max 15% of total
assets below B
No Limitation
PIMCO Global Bond Opportunities
(U.S. Dollar-Hedged)
U.S. and hedged non-U.S. intermediate maturity
fixed income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO Global Bond Opportunities
(Unhedged)
U.S. and non-U.S. intermediate maturity fixed
income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation
PIMCO Diversified Income
Investment grade corporate, high yield and
emerging market fixed income instruments
3 to 8 years
Max 10% below B
No Limitation
PIMCO Emerging Markets Local Currency
and Bond
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and fixed income instruments
+/-2 years of its
benchmark
Max 15% of total
assets below B
No Limitation(16)
PIMCO Emerging Markets Corporate
Bond
Diversified portfolio of fixed income
instruments economically tied to emerging
market countries
+/- 2 years of its
benchmark
Max 15% of total
assets below B
No Limitation
Absolute Return
PIMCO Dynamic Bond
Diversified portfolio of fixed income
instruments
(-3) to 8 years
Max 40% of total
assets below Baa
No Limitation(17)
PIMCO Strategic Bond
Diversified portfolio of fixed income
instruments
(-1) to 5 years
Max 20% of total
assets below Baa
No Limitation(18)
PIMCO Credit Opportunities Bond
Diversified portfolio of fixed income
instruments
0 to 6 years
Max 50% of total
assets below B-
No Limitation(5)
PIMCO TRENDS Managed Futures
Strategy
Financial and commodity-linked derivative
instruments selected by a quantitative strategy
and generally backed by a short to intermediate
duration portfolio which may consist of cash
equivalent securities and fixed income
instruments
N/A
No Limitation
No Limitation
PIMCO RAE Fundamental Advantage
PLUS
Long exposure to RAE US Large Model
Portfolio, short exposure to the S&P 500 Index,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(17)
PIMCO Climate Bond
Diversified portfolio of fixed income
instruments
2 to 8 years
Max 25% of total
assets below Baa
No Limitation(5)
Domestic
Equity-Related
PIMCO RAE PLUS
Exposure to RAE US Large Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(17)
PIMCO StocksPLUS® Small
Russell 2000® Index derivatives backed by a
diversified portfolio of actively managed fixed
income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS® Long Duration
S&P 500 Index derivatives backed by a
diversified portfolio of long-term fixed income
instruments
+/-2 years of
Bloomberg
Barclays
Long-Term
Government/Credit
Index(20)
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO StocksPLUS® Absolute Return
S&P 500 Index derivatives backed by a portfolio
of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(17)
PIMCO StocksPLUS®
S&P 500 Index derivatives backed by a portfolio
of short-term fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO RAE PLUS Small
Exposure to RAE US Small Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(13)
PIMCO RAE US
Exposure to RAE US Portfolio
N/A
N/A
0%
PIMCO RAE US Small
Exposure to RAE US Small Portfolio
N/A
N/A
0%

48  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
Equity-Related
PIMCO Dividend and Income
Exposure to RAE Income Global Portfolio in
Equity Sleeve; remainder of portfolio invests in
fixed income instruments of varying maturities
N/A
No Limitation
No Limitation
PIMCO RAE PLUS EMG
Exposure to RAE Emerging Markets Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO StocksPLUS® International
(Unhedged)
Non-U.S. equity derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS® International
(U.S. Dollar-Hedged)
Non-U.S. equity derivatives (hedged to
U.S. dollars) backed by a portfolio of fixed
income instruments.
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO RAE PLUS International
Exposure to RAE International Large Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE Worldwide Long/Short PLUS
Long exposure to RAE Low Volatility U.S. Model
Portfolio, RAE Low Volatility Intl Model Portfolio
and RAE Low Volatility EMG Model Portfolio,
short exposure to certain traditional
capitalization-weighted equity indexes,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE Emerging Markets
Exposure to RAE Emerging Markets Portfolio
N/A
N/A
No Limitation
PIMCO RAE International
Exposure to RAE International Portfolio
N/A
N/A
No Limitation
U.S. Government
Securities
PIMCO Government Money Market
U.S. government securities
≤ 60 days
dollar-weighted
average maturity
Min 97% of total
assets Prime 1; ≤ 3%
of total assets Prime 2
0%
Short Strategy
PIMCO StocksPLUS® Short
Short S&P 500 Index derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(17)
1
As rated by Moody's, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality.
2
Certain Underlying PIMCO Funds may invest beyond these limits in U.S. dollar-denominated instruments of non-U.S. issuers.
3
Such limitation shall not apply to the Fund's investments in mortgage- and asset-backed securities.
4
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 10% of its total assets.
5
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
6
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund. Information for the PIMCO Low Duration Credit Fund is effective as of May 3, 2021.
7
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 5% of its total assets.
8
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index.
9
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML Developed Markets High Yield Constrained (USD Hedged) Index.
10
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to within 10% (plus or minus) of the Fund's benchmark's foreign currency exposure.
11
The Fund may also invest up to an additional 5% of its total assets in mortgage-related high yield instruments rated below Baa.
12
Such limitation shall not apply to the Fund's investments in mortgage-related securities.
13
Within such limitation, the Fund may invest in mortgage-related securities rated below B.
14
The percentage limitation relates to Fixed Income Instruments of non-U.S. issuers denominated in any currency.
15
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or in Fixed Income Instruments denominated in the currencies of, emerging market countries, and in short-term investments.
16
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or Fixed Income Instruments denominated in the currencies of, emerging market countries and in Fixed Income Instruments, each of which may be represented by forwards or derivatives such as options, futures contracts or swap agreements.
17
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
18
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 25% of its total assets.
19
With respect to the Fund's fixed income investments, the Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
20
The Bloomberg Barclays Long-Term Government/Credit Index is an unmanaged index of U.S. Government or investment grade credit securities having a maturity of 10 years or more.

April 30, 2021 | PROSPECTUS  49

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Global Diversified Allocation Portfolio (Consolidated)
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$11.36
$0.30
$0.05
$0.35
$(0.33)
$(0.76)
$0.00
$(1.09)
12/31/2019
9.58
0.32
1.75
2.07
(0.29)
0.00
0.00
(0.29)
12/31/2018
10.97
0.27
(1.23)
(0.96)
(0.21)
(0.22)
0.00
(0.43)
12/31/2017
9.66
0.29
1.33
1.62
(0.31)
0.00
0.00
(0.31)
12/31/2016
9.13
0.16
0.55
0.71
(0.15)
(0.02)
(0.01)
(0.18)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratios shown do not include expenses of the investment companies in which the Portfolio may invest. See the Fees and Expenses note in the Notes to Financial Statements for more information regarding the expenses and any applicable fee waivers associated with these investments.

50  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets(d)
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.62
4.15%
$757,485
0.47%
1.00%
0.47%
1.00%
2.85%
23%
11.36
21.71
808,461
0.47
1.00
0.47
1.00
3.00
19
9.58
(8.94)
752,593
0.47
1.00
0.47
1.00
2.53
16
10.97
16.87
838,361
0.47
1.00
0.47
1.00
2.83
2
9.66
7.81
645,013
0.46
1.00
0.46
1.00
1.77
22

April 30, 2021 | PROSPECTUS  51

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2061F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
STRATEGIC ASSET ALLOCATION PORTFOLIO WITH DYNAMIC RISK MANAGEMENT
PIMCO Global Diversified Allocation Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Global Diversified Allocation Portfolio

Investment Objective
The Portfolio seeks to maximize risk-adjusted total return relative to a blend of 60% MSCI World Index/40% Bloomberg Barclays U.S. Aggregate Index.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.85%
Distribution and/or Service (12b-1) Fees
0.25%
Acquired Fund Fees and Expenses(1)
0.57%
Total Annual Portfolio Operating Expenses(2)
1.67%
Fee Waiver and/or Expense Reimbursement(3)
(0.53%)
Total Annual Portfolio Operating Expenses After Fee Waiver and/or
Expense Reimbursement
1.14%
1
Acquired Fund Fees and Expenses include interest expense of the Underlying PIMCO Funds of 0.04%. Interest expense can result from certain transactions within the Underlying PIMCO Funds and is separate from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense of the Underlying PIMCO Funds, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 1.10% for Advisor Class shares.
2
Total Annual Portfolio Operating Expenses do not match the Ratio of Expenses to Average Net Assets Excluding Waivers of the Portfolio, as set forth in the Financial Highlights table of the Portfolio’s prospectus, because the Ratio of Expenses to Average Net Assets Excluding Waivers reflects the operating expenses of the Portfolio and does not include Acquired Fund Fees and Expenses.
3
PIMCO has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the expenses attributable to the Management Fees of Underlying PIMCO Funds indirectly incurred by the Portfolio in connection with its investments in Underlying PIMCO Funds, to the extent the Portfolio’s Management Fees are greater than or equal to the Management Fees of the Underlying PIMCO Funds. This waiver renews annually for a full year unless terminated by PIMCO upon at least 30 days' notice prior to the end of the contract term. For purposes of the expense reduction described above, references to Underlying PIMCO Funds include funds of PIMCO ETF Trust.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any
variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$116
$475
$858
$1,932
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 23% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing in a combination of Acquired Funds and/or direct investments and utilizing hedging techniques to manage downside risks and total portfolio volatility. The Portfolio will invest under normal circumstances in a combination of affiliated funds registered under the Investment Company Act of 1940, as amended (the “1940 Act”), equity securities, Fixed Income Instruments, forwards and derivatives. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio may invest in Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end investment companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management (“Underlying PIMCO Funds”), and may also invest in other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds, which may or may not be registered under the 1940 Act (collectively, “Acquired Funds”). The Portfolio will invest in Acquired Funds, securities, instruments and other investments to the extent permitted under the 1940 Act, or any exemptive relief therefrom. To the extent the Portfolio invests in Underlying PIMCO Funds, PIMCO expects to select such Underlying PIMCO Funds without considering or canvassing the universe of available unaffiliated Acquired Funds. The Portfolio will invest either directly or indirectly (through a fund) in instruments that are economically tied to at least three countries (one of which may be the United States).
The Portfolio’s investments will be utilized, in part, in seeking to limit the Portfolio’s overall volatility. Volatility is a measure of the magnitude of up and down fluctuations in the value of a financial instrument over time and typically results from rapid price swings. Under normal conditions, the Portfolio will seek to target an annualized volatility level of approximately 10%. A higher volatility level indicates more frequent or rapid up and down fluctuations in the value of the Portfolio relative to a lower volatility level. For example, in a more volatile market environment, PIMCO may decrease long derivative positions in volatile assets or assume a short position through derivatives in such assets in an attempt to potentially reduce the Portfolio’s volatility. The Portfolio’s transactions used to target volatility are generally determined by

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

proprietary quantitative models that take into consideration factors that may include asset class volatilities and correlations. The proprietary quantitative models are developed and maintained by PIMCO, and are subject to change over time without notice in PIMCO’s discretion. PIMCO retains discretion to override a model’s recommendation. PIMCO’s use of Acquired Funds and direct investments in seeking to manage volatility will be consistent with the Portfolio’s target asset allocation guidelines described below. There can be no assurance that investment decisions made in seeking to manage Portfolio volatility will achieve the desired results.
On average, the Portfolio will target approximately 60% equity-related exposure and 40% Fixed Income Instruments-related exposure; however, the Portfolio may adjust its overall equity exposure in seeking to manage the Portfolio’s overall volatility. The Portfolio will normally limit its equity-related exposure to 15% to 80% of its total assets. The Portfolio will typically seek to gain equity-related exposure by investing (directly or indirectly through Acquired Funds) in derivatives, including, but not limited to, options, futures contracts or swap agreements, common stock, preferred securities and equity securities of real estate investment trusts. With respect to its direct or indirect (through a fund) investments in equity securities, there is no limitation on the market capitalization range of the issuers in which the Portfolio may invest. The Portfolio may invest up to 10% of its total assets in commodity-related investments (including investment in commodity-related Underlying PIMCO Funds). The Portfolio may invest, without limitation, in securities denominated in foreign currencies and in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 25% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest in such instruments without limitation subject to any applicable legal or regulatory limitation). In addition, the Portfolio may invest in both investment-grade securities and high yield securities (“junk bonds”), subject to a maximum of 10% of its total assets in securities rated below B by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may purchase and sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales.
As part of its investment process, PIMCO will seek to reduce exposure to certain downside risks by implementing various hedging transactions. These hedging transactions seek to reduce the Portfolio’s exposure to certain severe, unanticipated market events that could significantly detract from returns. The Portfolio’s hedging transactions are generally determined by a systematic process that seeks to maintain hedge efficacy while reducing the long-term cost of hedging. PIMCO retains discretion to override the output of the systematic process.
Additional information for the Underlying PIMCO Funds can be found in the Statement of Additional Information and/or the Underlying PIMCO Funds’ prospectuses and financial reports. Additional Underlying PIMCO Funds may be added or deleted in the future without shareholder notification.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio include risks from direct investments and/ or indirect exposure through investment in Acquired Funds. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are:
Allocation Risk:the risk that a Portfolio could lose money as a result of less than optimal or poor asset allocation decisions. The Portfolio could miss attractive investment opportunities by underweighting markets that subsequently experience significant returns and could lose value by overweighting markets that subsequently experience significant declines
Acquired Fund Risk:the risk that a Portfolio's performance is closely related to the risks associated with the securities and other investments held by the Acquired Funds and that the ability of a Portfolio to achieve its investment objective will depend upon the ability of the Acquired Funds to achieve their investment objectives
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield

April 30, 2021 | PROSPECTUS  2

PIMCO Global Diversified Allocation Portfolio

securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Model Risk:the risk that the Portfolio’s investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in the Portfolio
Commodity Risk:the risk that investing in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought,
floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Real Estate Risk:the risk that the Portfolio’s investments in Real Estate Investment Trusts (“REITs”) or real estate-linked derivative instruments will subject the Portfolio to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. A Portfolio’s investments in REITs or real estate-linked derivative instruments subject it to management and tax risks. In addition, privately traded REITs subject a Portfolio to liquidity and valuation risk
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Smaller Company Risk:the risk that the value of securities issued by a smaller company may go up or down, sometimes rapidly and

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

unpredictably as compared to more widely held securities, due to narrow markets and limited resources of smaller companies. A Portfolio’s investments in smaller companies subject it to greater levels of credit, market and issuer risk
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO, including the use of quantitative models or methods, will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Tax Risk:the risk that the tax treatment of swap agreements and other derivative instruments, such as commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures, may be affected by future regulatory or legislative changes that could affect whether income from such investments is “qualifying income” under Subchapter M of the Internal Revenue Code, or otherwise affect the character, timing and/or amount of the Portfolio’s taxable income or gains and distributions
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Value Investing Risk:a value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
Exchange-Traded Fund Risk:the risk that an exchange-traded fund may not track the performance of the index it is designed to track, among other reasons, because of exchange rules, market prices of shares of an exchange-traded fund may fluctuate rapidly and materially, or shares of an exchange-traded fund may trade significantly above or below net asset value, any of which may cause losses to the Portfolio invested in the exchange-traded fund
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that
currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The 60% MSCI World Index/40% Bloomberg Barclays U.S. Aggregate Index is a blended index. The MSCI World Index is a free float-adjusted market capitalization weighted index that is designed to measure the equity market performance of developed markets. The MSCI World Index consists of 23 developed market country indices. The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable, and dollar denominated. The Bloomberg Barclays U.S. Aggregate Index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.

April 30, 2021 | PROSPECTUS  4

PIMCO Global Diversified Allocation Portfolio

Calendar Year Total Returns — Advisor Class
Best Quarter
March 31, 2019
9.77%
Worst Quarter
March 31, 2020
-12.69%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Advisor Class Return
3.99%
7.66%
5.54%
4/30/2013
60% MSCI World Index/40%
Bloomberg Barclays U.S. Aggregate
Index (reflects no deductions for fees,
expenses or taxes)
13.31%
9.34%
7.66%
 
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Graham Rennison and Yang Lu. Mr. Rennison is a Senior Vice President of PIMCO, and he has managed the Portfolio since December 2015. Mr. Lu is a Vice President of PIMCO, and he has managed the Portfolio since April 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

5  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
As the Portfolio may invest in shares of Acquired Funds, including the Underlying PIMCO Funds, the risks of investing in the Portfolio may be closely related to the risks associated with the Acquired Funds, including Underlying PIMCO Funds, and their investments. However, as the Portfolio may also invest its assets directly in stocks or bonds of other issuers and in other instruments, such as forwards, options, futures contracts or swap agreements, the Portfolio may be directly exposed to certain risks described below. As such, unless stated otherwise, any reference in this section to “Portfolios” includes both the Portfolio and Acquired Funds. Where necessary in this section, the Portfolio is specifically referred to as the “Portfolio.”
Allocation Risk
The Portfolio’s investment performance depends upon how its assets are allocated and reallocated according to the Portfolio’s asset allocation targets and ranges. A principal risk of investing in the Portfolio is that PIMCO will make less than optimal or poor asset allocation decisions. PIMCO attempts to identify investment allocations that will provide consistent, quality performance for the Portfolio, but there is no guarantee that such allocation techniques will produce the desired results. It is possible that PIMCO will focus on an investment that performs poorly or underperforms other investments under various market conditions. You could lose money on your investment in the Portfolio as a result of these allocation decisions.
Acquired Fund Risk
Because the Portfolio may invest its assets in Acquired Funds, the risks associated with investing in the Portfolio may be closely related to the risks associated with the securities and other investments held by the Acquired Funds. The ability of the Portfolio to achieve its investment objective may depend upon the ability of the Acquired Funds to achieve their respective investment objectives. There can be no assurance that the investment objective of any Acquired Fund will be achieved.
The Portfolio’s net asset value (“NAV”) will fluctuate in response to changes in the NAVs of the Acquired Funds in which it invests. The extent to which the investment performance and risks associated with the Portfolio correlates to those of a particular Acquired Fund will depend upon the extent to which the Portfolio’s assets are allocated from time to time for investment in the Acquired Fund, which may vary. As discussed under “Description of Principal Risks—Market Risk,” because the NAV of the Portfolio is related to the NAVs of the Acquired Funds in which it invests, inaccuracies, delays or other disruptions in the calculation of an Acquired Fund’s NAV may adversely impact the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the NAV of the Portfolio’s shares.

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the

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Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio and certain Acquired Funds may rely on various third-party sources to calculate their respective NAVs. As a result, the Portfolio and such Acquired Funds are subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s and Acquired Funds' calculations of their NAVs, and such NAV calculation issues may result in inaccurately calculated NAVs, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. Also, because the NAV of the Portfolio is related to the NAVs of the Acquired Funds in which it invests, the Portfolio may be adversely impacted by such inaccuracies, delays or other disruptions in the calculation of an Acquired Fund's NAV. The Portfolio may be unable to recover any losses associated with such failures.

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Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the

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Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests. These factors include the possibility that the Portfolio's commodity derivatives positions, may have different roll dates, reset dates or contract months than those specified in a particular commodity index.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Model Risk
In making investment allocation decisions for a Portfolio or certain Underlying PIMCO Funds, as applicable, PIMCO or the Sub-Adviser, as applicable, may utilize quantitative models that may be proprietary or developed by third-parties. These models are used by PIMCO or the Sub-Adviser, as applicable, to determine (or assist in determining) the Portfolio’s or Underlying PIMCO Fund’s target asset allocation and to identify potentially attractive relative value and risk hedging strategies. The investment models used in making investment allocation decisions may not adequately take into account certain factors, may contain design flaws or faulty assumptions, and may rely on incomplete or inaccurate data, any of which may result in a decline in the value of an investment in a Portfolio or Underlying PIMCO Fund. There can be no assurance that the models used by PIMCO or the Sub-Adviser, as applicable, will remain viable, due to various factors, which may include the quality of the data input into the models and the

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assumptions underlying such models, which to varying degrees involve the exercise of judgment, as well as the possibility of errors in constructing or using the model. In addition, in constructing the underlying index of, or model portfolio for, an Underlying PIMCO Fund that seeks to track the investment results of such underlying index or model portfolio, the index provider or sub-adviser, as applicable, may utilize quantitative models or methodologies that may be proprietary or developed by third-parties. These models and methodologies are used to help determine the composition of the underlying index or model portfolio and may not adequately take into account certain factors, resulting in a decline in the value of the underlying index or model portfolio and, therefore, the Underlying PIMCO Fund.
Models rely on accurate market data inputs. If inaccurate market data is entered into a model, the resulting information will be incorrect. In addition, the models used may be predictive in nature and such models may result in an incorrect assessment of future events. The models evaluate securities or securities markets based on certain assumptions concerning the interplay of market factors. The markets or the prices of individual securities may be affected by factors not foreseen in developing the models. In addition, when relying on a quantitative model and/or data supplied by third parties, PIMCO or the Sub-Adviser may have less insight into the construction, coding or testing of the third-party model or data, and PIMCO and the Sub-Adviser will be exposed to systems, cyber security and other risks associated with the third party that provides the model or data.
The use of models can be complex and involves financial, economic, econometric and statistical theories, research and modeling; and the results of those processes must then be translated into computer code. Although PIMCO and the Sub-Adviser seek to hire individuals and/or third parties, as applicable, skilled in each of these functions and to provide appropriate levels of oversight, the complexity of the individual tasks, the difficulty of integrating such tasks, and the limited ability to perform “real world” testing of a model’s end product raises the chances that a finished model may contain an error; one or more of such errors could adversely affect a Portfolio’s or an Underlying PIMCO Fund’s performance.
Commodity Risk
The Portfolio’s investments in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments. Certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, may each concentrate its assets in a particular sector of the commodities market (such as oil, metal or agricultural products). As a result, certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, and, to the extent the Portfolio invests in certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund or PIMCO CommodityRealReturn Strategy Fund®, the Portfolio may be more susceptible to risks associated with those sectors. The prices for commodities in those sectors may fluctuate widely due to factors such as changes in value, supply and demand and governmental regulatory policies.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other

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asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invest exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Real Estate Risk
Investments in real estate investment trusts (“REITs”) or real estate-linked derivative instruments are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. An investment in a REIT or a real estate-linked derivative instrument that is linked to the value of a REIT is subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (the “Code”). In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. Finally, private REITs are not traded on a national securities exchange. As such, these products are generally illiquid. This reduces the ability of a Portfolio to redeem its investment early. Private REITs are also generally harder to value and may bear higher fees than public REITs.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In

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such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities (or the value of the Acquired Funds). Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.

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PIMCO Variable Insurance Trust

Smaller Company Risk
The general risks associated with fixed income securities and equity securities are particularly pronounced for securities issued by companies with smaller market capitalizations. These companies may have limited product lines, markets or financial resources or they may depend on a few key employees. As a result, they may be subject to greater levels of credit, market and issuer risk. Securities of smaller companies may trade less frequently and in lesser volumes than more widely held securities and their values may fluctuate more sharply than other securities. Companies with medium-sized market capitalizations may have risks similar to those of smaller companies.
Management Risk
The Portfolio and certain Acquired Funds are subject to management risk because they are actively managed investment portfolios. PIMCO, or in the case of a fund that is not managed by PIMCO, such other fund’s investment adviser and sub-adviser, as applicable, and each individual portfolio manager will apply investment techniques and risk analysis and will, in some cases, rely partially or entirely upon or be informed by one or more quantitative models in making investment decisions for the Portfolio and the Acquired Funds, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio or an Acquired Fund seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio or Acquired Fund. To the extent the Portfolio or Acquired Fund employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio or Acquired Fund. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Because a number of Underlying PIMCO Funds obtain exposure to certain proprietary model stock portfolios by investing in equity total return swaps based on such model portfolios, in other securities and instruments to replicate the performance of such model portfolios, or directly in the equity securities held in such model portfolios, such Underlying PIMCO Funds will be subject to the risks associated with the management of these proprietary model stock portfolios by the Sub-Adviser to such Underlying PIMCO Funds. Similarly, there can be no assurance that quantitative models or methods utilized by PIMCO or the Sub-Adviser or related data sources will always be available, and the loss of access to any such model(s) or data sources could have an adverse impact on the Underlying PIMCO Fund’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Risk
The PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds, gain exposure to the commodities markets through investments in commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures. Each of the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund may also gain exposure indirectly to commodity markets by investing in its respective subsidiary (each a “Subsidiary” and collectively, the “Subsidiaries”), which invests primarily in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and/or other Fixed Income Instruments. In order for the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”), each Underlying PIMCO Fund must derive at least 90 percent of its gross income each taxable year from certain qualifying sources of income.
As more fully described below under “Tax Consequences-A Note on the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds”, the Internal Revenue Service (the “IRS”) issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. The IRS has issued private letter rulings in which the IRS specifically concluded that income derived from an investment in a subsidiary will also constitute qualifying income. Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if an Underlying PIMCO Fund‘s income from an investment in the subsidiary is distributed annually or is derived with respect to the Underlying PIMCO Fund’s business of investing in securities. An IRS revenue procedure states that the IRS will not issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the Investment Company Act of 1940, as amended (the “1940 Act”).
The PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund will seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in their respective Subsidiaries. If the IRS were to determine that income derived from certain commodity-linked notes or from investments in a Subsidiary does not constitute qualifying income, certain Underlying PIMCO Funds, including the PIMCO CommodityRealReturn Strategy Fund and PIMCO CommoditiesPLUS® Strategy Fund, might be adversely affected and would be required to reduce their exposure to such investments which might result in difficulty in implementing their investment strategies and increased costs and taxes. The use of commodity index-linked notes and investments in a Subsidiary involve specific risks. See “Characteristics and Risks of Securities and Investment Techniques—Derivatives—A Note on the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds” below for further information regarding commodity index-linked notes, including the risks associated with these instruments. In addition, see “Characteristics and Risks of Securities and Investment Techniques-Investments in a Wholly-Owned Subsidiary” below for further information regarding the Subsidiaries, including the risks associated with investing in the Subsidiaries.
To the extent the Portfolio invests in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund®, or PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund, the use of the above noted investments by the Underlying PIMCO Fund could subject the shareholders of the Portfolio to risks similar to those borne by shareholders of the PIMCO CommodityRealReturn® Strategy and PIMCO Global Managed Asset Allocation Portfolios. See “Tax Consequences.”
Value Investing Risk
Value investing attempts to identify companies that are believed to be undervalued. Value stocks typically have prices that are low relative to factors such as the company’s earnings, cash flow or dividends. A value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur. A value investing style may perform better or worse than equity portfolios that focus on growth stocks or that have a broader investment style.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.

April 30, 2021 | PROSPECTUS  15

PIMCO Variable Insurance Trust

Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
Exchange-Traded Fund (“ETF”) Risk
Investments in ETFs entail certain risks. Investments in ETFs designed to track an index involve the risk that the ETF’s performance may not track the performance of the index the ETF is designed to track. This deviation may occur due to cash inflows and outflows from and to investors buying and redeeming shares or due to occasional differences between the composition of the index and the securities held by the ETF. In addition, investments in ETFs involve the risk that the market prices of ETF shares will fluctuate, sometimes rapidly and materially, in response to changes in the ETF’s NAV, the value of ETF holdings and supply and demand for ETF shares. Although ETFs will generally trade close to NAV, market volatility, lack of an active trading market for ETF shares, disruptions at market participants (such as Authorized Participants or market makers) and any disruptions in the ordinary functioning of the creation/redemption process may result in ETF shares trading significantly above (at a “premium”) or below (at a “discount”) NAV. Significant losses may result when transacting in ETF shares in these and other circumstances.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

16  Prospectus | PIMCO Variable Insurance Trust

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.85% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.45% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.40% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Fund of Funds Fees
The Portfolio is permitted to invest in Underlying PIMCO Funds, which, for the Portfolio, is defined to include Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end investment companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. The Portfolio is further permitted to invest in Acquired Funds, which, for the Portfolio, is defined to include the Underlying PIMCO Funds and other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds, which may or may not be registered under the 1940 Act.
The Portfolio pays advisory and supervisory and administrative fees directly to PIMCO at an annual rate stated above, based on the average daily net assets attributable in the aggregate to the Portfolio’s Advisor Class shares. The Portfolio also indirectly pays its proportionate share of the advisory, supervisory and administrative and management fees charged by PIMCO to the Underlying PIMCO Funds and, to the extent not included among the Underlying PIMCO Funds, funds of PIMCO ETF Trust in which the Portfolio invests (collectively, “Underlying PIMCO Fund Fees”).
PIMCO has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, to the extent necessary, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the Underlying PIMCO Fund Fees indirectly incurred by the Portfolio in connection with its investments in Underlying PIMCO Funds (for purposes of this expense reduction, this term includes funds of PIMCO ETF Trust), to the extent the Portfolio's advisory fee or advisory fee and supervisory and administrative fee, taken together, are greater than or equal to the Underlying PIMCO Fund Fees. This waiver will automally renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the current term.
The Acquired Fund Fees and Expenses shown in the Annual Portfolio Operating Expenses table for the Portfolio may be higher than the Underlying PIMCO Fund Fees used for purposes of the Expense Reduction shown in that table due to differences in the methods of calculation. The Acquired Fund Fees and Expenses, as required to be shown in the Annual Portfolio Operating Expenses table, are calculated using the total operating expenses for each Underlying PIMCO Fund (or any unaffiliated funds) over the Portfolio’s average net assets. The Underlying PIMCO Fund Fees that are used for purposes of implementing the expense reduction described above are calculated using the advisory and supervisory and administrative fees for each Underlying PIMCO Fund (and any unaffiliated funds) over the total assets invested in Underlying PIMCO Funds. Thus, the Acquired Fund Fees and Expenses listed in the Annual Portfolio Operating Expenses table will typically be higher than the Underlying PIMCO Fund Fees used to calculate the Expense Reduction when the Portfolio employs leverage as an investment strategy.
The expenses associated with investing in a fund of funds are generally higher than those for mutual funds that do not invest in other funds. The cost of investing in the Portfolio will generally be higher than the cost of investing in a portfolio that invests directly in individual stocks and bonds. By investing in the Portfolio, an investor will indirectly bear fees and expenses charged by non-PIMCO Acquired Funds (and may indirectly bear a portion of the fees and expenses charged by Underlying PIMCO Funds, to the extent such fees and expenses are not waived or reimbursed pursuant to applicable waiver and reimbursement agreements), in addition to the Portfolio’s direct fees and expenses. In addition, the use of a fund of funds structure could affect the timing, amount and character of distributions to shareholders and may therefore increase the amount of taxes payable by shareholders. The Portfolio invests, to the extent it invests in Underlying PIMCO Funds, invests in Institutional Class or Class M shares of the Underlying PIMCO Funds, which are not subject to any sales charges or distribution (12b-1) fees.
The following table summarizes the annual expenses borne by Institutional Class or Class M shareholders of the Underlying PIMCO Funds. Because the Portfolio, to the extent it invests in Underlying PIMCO Funds, invests in Institutional Class or Class M shares of the Underlying PIMCO Funds, shareholders of the Portfolio would indirectly bear a proportionate share of these expenses, depending upon how the Portfolio’s assets are allocated from time to time among the Underlying PIMCO Funds.
For a complete description of an Underlying PIMCO Fund, please see the Underlying PIMCO Fund’s prospectus or offering memorandum, as applicable. For a summary description of the Underlying PIMCO Funds, please see the “Descriptions of the Underlying PIMCO Funds” section in this prospectus.
Annual Underlying PIMCO Fund Expenses
(Based on the average daily net assets attributable to an Underlying PIMCO Fund’s Institutional Class shares (or Class M shares in the case of the PIMCO Government Money Market Fund )).
Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO California Intermediate Municipal Bond Fund
0.445%
0.00%
0.445%
PIMCO California Municipal Bond Fund
0.44%
0.02%
0.46%
PIMCO California Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Climate Bond Fund
0.50%
0.00%
0.50%
PIMCO CommoditiesPLUS® Strategy Fund
0.74%
0.27%
1.01%(3)
PIMCO CommodityRealReturn Strategy Fund®
0.74%
0.76%
1.50%(4)

April 30, 2021 | PROSPECTUS  19

PIMCO Variable Insurance Trust

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO Credit Opportunities Bond Fund
0.90%
0.02%
0.92%
PIMCO Diversified Income Fund
0.75%
0.04%
0.79%
PIMCO Dividend and Income Fund
0.75%
0.05%
0.80%(5)
PIMCO Dynamic Bond Fund
0.80%
0.05%
0.85%
PIMCO Emerging Markets Bond Fund
0.83%
0.05%
0.88%
PIMCO Emerging Markets Corporate Bond Fund
0.90%
0.12%
1.02%
PIMCO Emerging Markets Currency and Short-Term Investments Fund
0.85%
0.03%
0.88%
PIMCO Emerging Markets Local Currency and Bond Fund
0.90%
0.80%
1.70%
PIMCO ESG Income Fund
0.50%
0.07%
0.57%(6)
PIMCO Extended Duration Fund
0.50%
1.21%
1.71%
PIMCO Global Advantage® Strategy Bond Fund
0.65%
0.21%
0.86%
PIMCO Global Bond Opportunities Fund (U.S. Dollar-Hedged)
0.55%
0.04%
0.59%
PIMCO Global Bond Opportunities Fund (Unhedged)
0.55%
0.12%
0.67%
PIMCO GNMA and Government Securities Fund
0.50%
0.33%
0.83%
PIMCO Government Money Market Fund
0.18%
0.00%
0.18%(7)
PIMCO High Yield Fund
0.55%
0.02%
0.57%
PIMCO High Yield Municipal Bond Fund
0.55%
0.08%
0.63%
PIMCO High Yield Spectrum Fund
0.60%
0.02%
0.62%
PIMCO Income Fund
0.50%
0.59%
1.09%
PIMCO International Bond Fund (U.S. Dollar-Hedged)
0.50%
0.10%
0.60%
PIMCO International Bond Fund (Unhedged)
0.50%
0.13%
0.63%
PIMCO Investment Grade Credit Bond Fund
0.50%
0.35%
0.85%
PIMCO Long Duration Total Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term Credit Bond Fund
0.55%
0.29%
0.84%
PIMCO Long-Term Real Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term U.S. Government Fund
0.475%
1.38%
1.855%
PIMCO Low Duration Credit Fund(8)
0.70%
0.05%
0.75%
PIMCO Low Duration ESG Fund
0.50%
0.08%
0.58%
PIMCO Low Duration Fund
0.46%
0.41%
0.87%
PIMCO Low Duration Fund II
0.50%
0.03%
0.53%
PIMCO Low Duration Income Fund
0.50%
0.05%
0.55%
PIMCO Moderate Duration Fund
0.46%
0.15%
0.61%
PIMCO Mortgage Opportunities and Bond Fund
0.60%
1.22%
1.82%
PIMCO Mortgage-Backed Securities Fund
0.50%
0.25%
0.75%
PIMCO Municipal Bond Fund
0.44%
0.07%
0.51%
PIMCO National Intermediate Municipal Bond Fund
0.45%
0.00%
0.45%
PIMCO New York Municipal Bond Fund
0.445%
0.05%
0.495%
PIMCO Preferred and Capital Securities Fund
0.79%
0.09%
0.88%(9)
PIMCO RAE Emerging Markets Fund
0.75%
0.02%
0.77%(10)
PIMCO RAE Fundamental Advantage PLUS Fund
0.89%
0.07%
0.96%
PIMCO RAE International Fund
0.50%
0.02%
0.52%(5)
PIMCO RAE PLUS EMG Fund
1.10%
0.21%
1.31%
PIMCO RAE PLUS Fund
0.79%
0.08%
0.87%
PIMCO RAE PLUS International Fund
0.82%
0.05%
0.87%
PIMCO RAE PLUS Small Fund
0.84%
0.09%
0.93%
PIMCO RAE US Fund
0.40%
0.02%
0.42%(5)
PIMCO RAE US Small Fund
0.50%
0.04%
0.54%
PIMCO RAE Worldwide Long/Short PLUS Fund
1.19%
0.09%
1.28%
PIMCO Real Return Fund
0.45%
0.08%
0.53%
PIMCO RealEstateRealReturn Strategy Fund
0.74%
1.36%
2.10%
PIMCO Short Asset Investment Fund
0.34%
0.02%
0.36%
PIMCO Short Duration Municipal Income Fund
0.33%
0.00%
0.33%

20  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO Short-Term Fund
0.45%
0.10%
0.55%
PIMCO StocksPLUS® Absolute Return Fund
0.64%
0.08%
0.72%
PIMCO StocksPLUS® Fund
0.50%
0.06%
0.56%
PIMCO StocksPLUS® International Fund (U.S. Dollar-Hedged)
0.75%
0.25%
1.00%
PIMCO StocksPLUS® International Fund (Unhedged)
0.64%
0.38%
1.02%
PIMCO StocksPLUS® Long Duration Fund
0.59%
0.42%
1.01%
PIMCO StocksPLUS® Short Fund
0.64%
0.45%
1.09%
PIMCO StocksPLUS® Small Fund
0.69%
0.06%
0.75%
PIMCO Strategic Bond Fund
0.55%
0.02%
0.57%(11)
PIMCO Total Return ESG Fund
0.50%
0.46%
0.96%
PIMCO Total Return Fund
0.46%
0.24%
0.70%
PIMCO Total Return Fund II
0.50%
0.26%
0.76%
PIMCO Total Return Fund IV
0.50%
0.30%
0.80%
PIMCO TRENDS Managed Futures Strategy Fund
1.40%
0.29%
1.69%(12)
1
“Management Fees” reflects an advisory fee and a supervisory and administrative fee payable by an Underlying PIMCO Fund to PIMCO.
2
Other Expenses include expenses such as organizational expenses, interest expense, taxes, governmental fees, pro rata Trustees' fees and acquired fund fees and expenses attributable to the Institutional Class or Class M shares or the Fund in the case of exchange-traded funds of the PIMCO ETF Trust or PIMCO Equity Series.
3
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund III Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
4
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund I Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
5
PIMCO has contractually agreed, through October 31, 2021, to waive a portion of the Fund's supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund's organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Equity Series at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
6
PIMCO has contractually agreed, through July 31, 2022, to waive a portion of the Fund’s supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
7
To maintain certain net yields for the Fund, PIMCO or its affiliates may temporarily and voluntarily waive, reduce or reimburse all or any portion of the Fund's fees and expenses.
8
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund.
9
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Capital Securities Fund (Cayman) Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
10
PIMCO has contractually agreed, through July 31, 2022, to reduce its supervisory and administrative fee for each share class of the Fund by 0.05% of the average daily net assets attributable to the applicable class of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years from the date of waiver.
11
PIMCO has contractually agreed, through July 31, 2022, to reduce its advisory fee by 0.10% of the average daily net assets of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years.
12
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund VIII, Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.

April 30, 2021 | PROSPECTUS  21

PIMCO Variable Insurance Trust

Individual Portfolio Managers
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Global Diversified Allocation
Yang Lu
4/19
Vice President, PIMCO. Mr. Lu is a portfolio manager on the quantitative portfolio
management team in the Newport Beach office. Prior to joining PIMCO in 2018, he was an
analyst at Hutchin Hill Capital, responsible for developing and managing quant equity
market neutral strategies. He has investment experience since 2014 and holds an
undergraduate degree in mathematics and economics from Williams College.
PIMCO Global Diversified Allocation
Graham A. Rennison
12/15
Senior Vice President, PIMCO. Mr. Rennison is a member of the quantitative portfolio
management group, focusing on multi-asset class systematic strategies. Prior to joining
PIMCO in 2011, Mr. Rennison was associated with Barclays Capital and Lehman Brothers,
researching and publishing widely on quantitative strategies in the credit markets.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

22  Prospectus | PIMCO Variable Insurance Trust

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PIMCO Variable Insurance Trust

Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

24  Prospectus | PIMCO Variable Insurance Trust

Prospectus

From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

April 30, 2021 | PROSPECTUS  25

PIMCO Variable Insurance Trust

thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

26  Prospectus | PIMCO Variable Insurance Trust

Prospectus

circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

April 30, 2021 | PROSPECTUS  27

PIMCO Variable Insurance Trust

the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
A Note on the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund.The Portfolio may invest in the PIMCO CommoditiesPLUS® Strategy Fund, PIMCO CommodityRealReturn Strategy Fund® and PIMCO TRENDS Managed Futures Strategy Fund, each an Underlying PIMCO Fund. One of the requirements for favorable tax treatment as a regulated investment company under the Code is that each Underlying PIMCO Fund derive at least 90% of its gross income from certain qualifying sources of income. The IRS has issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. As such, each Underlying PIMCO

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Fund’s ability to utilize commodity-linked swaps as part of its investment strategy is limited to a maximum of 10 percent of its gross income.
However, in a subsequent revenue ruling, the IRS provides that income from alternative investment instruments (such as certain commodity index-linked notes) that create commodity exposure may be considered qualifying income under the Code. The IRS has also issued a private letter ruling to the Underlying PIMCO Funds in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued another private letter ruling to each Underlying PIMCO Fund in which the IRS specifically concluded that income derived from the Underlying PIMCO Fund’s investment in its Subsidiary will also constitute qualifying income to the Underlying PIMCO Fund, even if the Subsidiary itself owns commodity linked swaps. Each Underlying PIMCO Fund will continue to seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in its Subsidiary.
Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if an Underlying PIMCO Fund‘s income from an investment in the subsidiary is derived with respect to the Underlying PIMCO Fund’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the 1940 Act. In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings. There can be no assurance that the IRS will not change its position with respect to some or all of these conclusions or that future legislation will not adversely impact the tax treatment of each Underlying PIMCO Fund’s commodity-linked investments. If the IRS were to change or reverse its position, or if future legislation adversely affected the tax treatment of the commodity-linked investments of each Underlying PIMCO Fund, there would likely be a significant adverse impact on the Underlying PIMCO Fund, including the possibility of failing to qualify as a regulated investment company. If an Underlying PIMCO Fund did not qualify as a regulated investment company for any taxable year, its taxable income would be subject to tax at the Underlying PIMCO Fund level at regular corporate tax rates (without reduction for distributions to shareholders) and to a further tax at the shareholder level when such income is distributed.
Furthermore, the tax treatment of commodity-linked notes, other commodity-linked derivatives, and an Underlying PIMCO Fund’s investments in its Subsidiary may otherwise be adversely affected by future legislation, court decisions, Treasury Regulations and/or guidance issued by the IRS. Such developments could affect the character, timing and/or amount of the Underlying PIMCO Fund’s taxable income or any distributions made by the Underlying PIMCO Fund or result in the inability of the Underlying PIMCO Fund to operate as described in its prospectus.
A Note on the PIMCO CommodityRealReturn Strategy Fund®, an Underlying PIMCO Fund.Periodic adjustments for
inflation to the principal amount of an inflation-indexed bond may give rise to original issue discount, which will be includable in the Underlying PIMCO Fund’s gross income. Due to original issue discount, the Underlying PIMCO Fund may be required to make annual distributions to shareholders that exceed the cash received, which may cause the Underlying PIMCO Fund to liquidate certain investments when it is not advantageous to do so. Also, if the principal value of an inflation-indexed bond is adjusted downward due to deflation, amounts previously distributed in the taxable year may be characterized in some circumstances as a return of capital.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
As the Portfolio may invest in shares of the Acquired Funds, the risks of investing in the Portfolio may be closely related to the risks associated with the Acquired Funds and their investments. However, as the Portfolio may also invest its assets directly in Fixed Income Instruments, equity securities, forwards or derivatives, such as options, futures contracts or swap agreements, other affiliated or unaffiliated funds, and other investments, the Portfolio may be directly exposed to certain risks described below.
This section provides additional information about some of the principal investments and related risks of the Portfolio and of certain Acquired Funds described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio and certain Acquired Funds from time to time. Generally, the characteristics and risks of securities and investment techniques that may be used by the Acquired Funds from time to time are similar to those described below. However, the risks associated with an Acquired Fund’s investments are described more fully in each Acquired Fund’s prospectus. Accordingly, please see an Acquired Fund’s prospectus for a more complete description of the Acquired Fund and the risks associated with its investments.
Most of these securities and investment techniques described herein are discretionary, which means that PIMCO, or in the case of a fund that is not managed by PIMCO, such fund’s investment adviser and sub-adviser, as applicable, can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio or Acquired Funds. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives

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and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by a Portfolio and the results achieved by a Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to a Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact a Portfolio’s portfolio management. For example, a Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause Portfolios to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase a Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause a Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect a Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other
shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for an Underlying PIMCO Fund, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Underlying PIMCO Fund’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;

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delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of
U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain

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municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.

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Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued
mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to

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purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to
real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate

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inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Volatility
Volatility measures the variability in the price of an investment over time. A higher volatility level signifies an investment’s value may fluctuate over a larger range within a short period of time, either up or down. A lower volatility level means an investment’s value is more likely to change within a narrower range, or less frequently, over time. The more volatile the portfolio holdings of the Portfolio, the less predictable the returns for the Portfolio. Higher volatility levels may indicate heightened risk of losses.
PIMCO’s use of investments in seeking to manage the Portfolio‘s volatility will be consistent with the Portfolio’s asset allocation guidelines. Although asset allocation cannot eliminate investment risk or losses, it may provide opportunities to manage a Portfolio’s volatility relative to a Portfolio’s target annualized volatility level.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The

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income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this Prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions. Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights. Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time. In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In
such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
While certain Underlying PIMCO Funds will generally invest in equity derivatives, each such Underlying PIMCO Fund may invest without limit directly in equity securities, including common stocks, preferred securities and convertible securities. In addition, the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, each an Underlying PIMCO Fund, may invest in equity securities of issuers in commodity-related industries, and the PIMCO RealEstateRealReturn Strategy Fund, an Underlying PIMCO Fund, may invest in REITs and equity securities of issuers in real estate-related industries. The Portfolio may also invest directly in equity securities. When investing directly in equity securities, the Portfolio will not be limited to only those equity securities with any particular weighting in the Portfolio’s benchmark index, if any. Generally, the Portfolio may consider investing directly in equity securities when derivatives on the underlying securities appear to be overvalued.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and

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certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and
dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the

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laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate
significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.

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Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of

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the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to
use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the

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availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
A Note on the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds. In light of relevant IRS guidance, as discussed above under “Tax Consequences-A Note on the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds,” the Underlying PIMCO Funds will seek to gain exposure to the commodity markets primarily through investments in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices, and through investments in their respective Subsidiary (as discussed below). The Underlying PIMCO Funds may also invest in commodity-linked notes with principal and/or coupon payments linked to the value of particular commodities or commodity futures contracts, or a subset of commodities and commodities futures contracts. These notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in response to changes in the underlying commodity, commodity futures contract, subset of commodities, subset of commodities futures contracts or commodity index.
These notes expose the Underlying PIMCO Funds economically to movements in commodity prices. These notes also are subject to risks, such as credit, market and interest rate risks, that in general affect the values of debt securities. In addition, these notes are often leveraged, increasing the volatility of each note’s market value relative to changes in the underlying commodity, commodity futures contract or commodity index. Therefore, at the maturity of the note, the Underlying PIMCO Fund may receive more or less principal than it originally invested. The Underlying PIMCO Funds might receive interest payments on the note that are more or less than the stated coupon interest payments.
The Underlying PIMCO Funds may also invest in other commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures. The value of a commodity-linked derivative investment generally is based upon the price movements of a physical commodity (such as energy, mineral, or agricultural products), a commodity futures contract, a subset of commodities, a subset of
commodities futures contracts or commodity index, or other economic variable based upon changes in the value of commodities or the commodities markets.
Options transactions may be effected on exchanges or in the OTC market. When OTC options are purchased, the Portfolio’s portfolio bears the risk that the counterparty that wrote the option will be unable or unwilling to perform its obligations under the option contract. Options may also be illiquid and, in such cases, the Portfolio may have difficulty closing out its position. OTC options also may include options on baskets of specific securities.
Many swap transactions are privately negotiated agreements between an Underlying PIMCO Fund and a counterparty to exchange or swap investment cash flows or assets at specified intervals in the future. The obligations may extend beyond one year. There is often no central exchange for swap transactions and therefore they can be less liquid investments than exchange-traded instruments. The Dodd-Frank Act and related regulatory developments require the clearing and exchange-trading of certain standardized OTC derivative instruments that the CFTC and SEC have defined as “swaps.” The CFTC has implemented mandatory exchange-trading and clearing requirements under the Dodd-Frank Act and the CFTC continues to approve contracts for central clearing. Uncleared swaps are subject to margin requirements that are being implemented on a phased-in basis. The investment adviser will continue to monitor these developments, particularly to the extent regulatory changes affect a Portfolio’s ability to enter into swap agreements.
As described below under “Characteristics and Risks of Securities and Investment Techniques-Investments in the Wholly-Owned Subsidiary,” each Underlying PIMCO Fund may gain exposure to commodity markets by investing in its respective Subsidiary. It is expected that the Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments.
The IRS issued a revenue ruling that limits the extent to which the Underlying PIMCO Funds may invest directly in commodity-linked swaps or certain other commodity-linked derivatives. Each Subsidiary, on the other hand, may invest in these commodity-linked derivatives generally without limitation. See “Tax Consequences-A Note on the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds” above for further information.
Investments in a Wholly Owned Subsidiary
Investments in its respective Subsidiary are expected to provide the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund with exposure to the commodity markets within the limitations of Subchapter M of the Code and recent IRS revenue rulings, as discussed above under “Tax Consequences-A Note on the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, Underlying PIMCO Funds.”

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It is expected that each Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments. Although the Underlying PIMCO Funds may enter into these commodity-linked derivative instruments directly, each Underlying PIMCO Fund will likely gain exposure to these derivative instruments indirectly by investing in its respective Subsidiary. To the extent that PIMCO believes that these commodity-linked derivative instruments are better suited to provide exposure to the commodities market than commodity index-linked notes, each Underlying PIMCO Fund’s investment in its Subsidiary will likely increase. Each Subsidiary will also invest in inflation indexed securities and/or other Fixed Income Instruments, which are intended to serve as margin or collateral for the Subsidiary’s derivatives position, common and preferred securities as well as convertible securities of issuers in commodity-related industries, collateralized debt obligations, event-linked bonds and event-linked swaps. To the extent that the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund invests in its respective Subsidiary, it may be subject to the risks associated with those derivative instruments and other securities, which are discussed elsewhere in this prospectus.
While each Subsidiary may be considered similar to an investment company, it is not registered under the 1940 Act and, unless otherwise noted in the prospectus, is not subject to all of the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund and/or each Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund and, to the extent the Portfolio invests in the PIMCO CommodityRealReturn Strategy Fund® or PIMCO CommoditiesPLUS® Strategy Fund, the Portfolio. Changes in the laws of the United States and/ or the Cayman Islands could adversely affect the performance of the Portfolio and/or a Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets

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determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in Underlying PIMCO Funds and, to the extent permitted by the 1940 Act or exemptive relief therefrom, other affiliated and unaffiliated funds, which may or may not be registered under the 1940 Act, such as open-end or closed-end management investment companies, exchange-traded funds and exchange-traded vehicles. Other unaffiliated investment companies are not required to make their shares available for purchase by the Portfolio, and there is no guarantee that such investment will be, or will continue to be available. Each Underlying PIMCO Fund may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio and each Underlying PIMCO Fund may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws.

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To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective.
Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. In addition to indirectly bearing the expenses associated with portfolio turnover of the Acquired Funds, Portfolio will directly bear these expenses to the extent that it invests in other securities and instruments. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objectives of the Portfolio and certain Underlying PIMCO Funds are non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval. The investment objectives of certain Underlying PIMCO Funds are fundamental and may not be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes

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in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, sub-advisers, administrators, transfer agents, custodians, distributors and other third parties), trading
counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Descriptions of the Underlying PIMCO Funds
The Portfolio may invest its assets in some or all of the Underlying PIMCO Funds, which, for the Portfolio, is defined to include Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end investment companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. The Portfolio is further permitted to invest in Acquired Funds, which, for the Portfolio, is defined to include the Underlying PIMCO Funds and other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds, which may or may not be registered under the 1940 Act. Because the Underlying PIMCO Funds are not offered in this prospectus, the following provides a general description of the main investments and other information about the Underlying PIMCO Funds. At the discretion of PIMCO and without shareholder approval, the Portfolio may invest in additional Underlying PIMCO Funds created in the future. For a complete description of an Underlying PIMCO Fund, please see that Fund’s Institutional Class or Class M prospectus, which is incorporated herein by reference and is available free of charge by telephoning 1-800-927-4648.
Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Short Duration
PIMCO Low Duration Income
Short maturity fixed income instruments
0 to 3 years
Max 30% of total
assets below Baa(3)
No Limitation(4)
PIMCO Short Asset Investment
Money market instruments and short maturity
fixed income instruments
≤ 1.5 years
Baa to Aaa
0%
PIMCO Short-Term
Money market instruments and short maturity
fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below Baa
0-10% of total
assets(5)
PIMCO Low Duration
Short maturity fixed income instruments
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration II
Short maturity fixed income instruments with
quality and non-U.S. issuer restrictions
1 to 3 years
A to Aaa
0%
PIMCO Low Duration ESG
Short maturity fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration Credit(6)
Diversified portfolio of fixed income
instruments
0 to 3 years
Max 10% of total
assets below Caa
0-25% of total
assets(7)
Intermediate
Duration
PIMCO Moderate Duration
Short and intermediate maturity fixed income
instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO GNMA and Government
Securities
Short and intermediate maturity
mortgage-related fixed income securities issued
by the Government National Mortgage
Association and U.S. government securities
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa
0%
PIMCO High Yield
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(8) max
20% of total assets
Caa or below
0-20% of total
assets(5)
PIMCO High Yield Spectrum
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(9)
No Limitation(10)
PIMCO Mortgage-Backed Securities
Short and intermediate maturity
mortgage-related fixed income instruments
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa(11)
0%
PIMCO Total Return
Intermediate maturity fixed income instruments
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return II
Intermediate maturity fixed income instruments
with quality and non-U.S. issuer restrictions
+/-2 years of its
benchmark
Baa to Aaa
0%
PIMCO Total Return ESG
Intermediate maturity fixed income instruments
with prohibitions on firms engaged in socially
sensitive practices
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return IV
Intermediate maturity fixed income instruments
+/-1.5 years of its
benchmark
Baa to Aaa
0-15% of total
assets(7)
PIMCO Investment Grade Credit Bond
Investment grade fixed income securities
+/-2 years of its
benchmark
Max 15% of total
assets below Baa
0-30% of total
assets(5)

46  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Long Duration
PIMCO Long Duration Total Return
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Extended Duration
Long-term maturity fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO Long-Term U.S. Government
Long-term maturity fixed income securities
≥ 8 years
A to Aaa; max 25% Aa;
max 10% A
0%
PIMCO Mortgage Opportunities and
Bond
Mortgage-related assets and fixed income
instruments
(-1) to 8 years
Max 50% of total
assets below Baa(12)
0%
PIMCO Long-Term Credit Bond
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
B to Aaa; max 20% of
total assets below Baa
0-30% of total
assets(5)
Income
PIMCO ESG Income
Broad range of fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Income
Broad range of fixed income instruments
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Preferred and Capital Securities
Capital securities and preferred securities
+/-2 years of its
benchmark
No Limitation
No Limitation(4)
Inflation-Related
PIMCO Real Return
Inflation-indexed fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO Long-Term Real Return
Inflation-indexed fixed income securities
+/-4 years of its
benchmark
B to Aaa; max 20% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO CommoditiesPLUS® Strategy
Commodity-linked derivative instruments
backed by an actively managed low volatility
portfolio of fixed income instruments
≤ 1 year
Max 10% of total
assets below Baa
0-20%(4)
PIMCO CommodityRealReturn Strategy®
Commodity-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO RealEstateRealReturn Strategy
Real estate-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
Tax Exempt
PIMCO California Short Duration
Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal and California
income tax)
≤ 3 years
Caa to Aaa; max 10%
of total assets below
Baa
0%
PIMCO California Municipal Bond
Municipal securities (exempt from federal and
California income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO Short Duration Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal income tax)
≤ 3 years
Baa to Aaa
0%
PIMCO California Intermediate Municipal
Bond
Intermediate maturity municipal securities
(exempt from federal and California income
tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO National Intermediate Municipal
Bond
Municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO New York Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal and New York
income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO High Yield Municipal Bond
Intermediate to long-term maturity high yield
municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
No Limitation
0%

April 30, 2021 | PROSPECTUS  47

PIMCO Variable Insurance Trust

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
PIMCO Emerging Markets Bond
Emerging market fixed income instruments
+/- 2 years of its
benchmark
Max 15% of total
assets below B
≥ 80% of assets(14)
PIMCO Emerging Markets Currency and
Short-Term Investments
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and short-term investments
≤ 2 years
Max 15% of total
assets below B
No Limitation(15)
PIMCO International Bond
(U.S. Dollar-Hedged)
Intermediate maturity hedged non-U.S. fixed
income instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO International Bond (Unhedged)
Intermediate maturity non-U.S. fixed income
instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation
PIMCO Global Advantage® Strategy
Bond
U.S. and non-U.S. fixed income instruments
≤ 8 years
Max 15% of total
assets below B
No Limitation
PIMCO Global Bond Opportunities
(U.S. Dollar-Hedged)
U.S. and hedged non-U.S. intermediate maturity
fixed income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO Global Bond Opportunities
(Unhedged)
U.S. and non-U.S. intermediate maturity fixed
income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation
PIMCO Diversified Income
Investment grade corporate, high yield and
emerging market fixed income instruments
3 to 8 years
Max 10% below B
No Limitation
PIMCO Emerging Markets Local Currency
and Bond
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and fixed income instruments
+/-2 years of its
benchmark
Max 15% of total
assets below B
No Limitation(16)
PIMCO Emerging Markets Corporate
Bond
Diversified portfolio of fixed income
instruments economically tied to emerging
market countries
+/- 2 years of its
benchmark
Max 15% of total
assets below B
No Limitation
Absolute Return
PIMCO Dynamic Bond
Diversified portfolio of fixed income
instruments
(-3) to 8 years
Max 40% of total
assets below Baa
No Limitation(17)
PIMCO Strategic Bond
Diversified portfolio of fixed income
instruments
(-1) to 5 years
Max 20% of total
assets below Baa
No Limitation(18)
PIMCO Credit Opportunities Bond
Diversified portfolio of fixed income
instruments
0 to 6 years
Max 50% of total
assets below B-
No Limitation(5)
PIMCO TRENDS Managed Futures
Strategy
Financial and commodity-linked derivative
instruments selected by a quantitative strategy
and generally backed by a short to intermediate
duration portfolio which may consist of cash
equivalent securities and fixed income
instruments
N/A
No Limitation
No Limitation
PIMCO RAE Fundamental Advantage
PLUS
Long exposure to RAE US Large Model
Portfolio, short exposure to the S&P 500 Index,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(17)
PIMCO Climate Bond
Diversified portfolio of fixed income
instruments
2 to 8 years
Max 25% of total
assets below Baa
No Limitation(5)
Domestic
Equity-Related
PIMCO RAE PLUS
Exposure to RAE US Large Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(17)
PIMCO StocksPLUS® Small
Russell 2000® Index derivatives backed by a
diversified portfolio of actively managed fixed
income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS® Long Duration
S&P 500 Index derivatives backed by a
diversified portfolio of long-term fixed income
instruments
+/-2 years of
Bloomberg
Barclays
Long-Term
Government/Credit
Index(20)
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO StocksPLUS® Absolute Return
S&P 500 Index derivatives backed by a portfolio
of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(17)
PIMCO StocksPLUS®
S&P 500 Index derivatives backed by a portfolio
of short-term fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO RAE PLUS Small
Exposure to RAE US Small Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(13)
PIMCO RAE US
Exposure to RAE US Portfolio
N/A
N/A
0%
PIMCO RAE US Small
Exposure to RAE US Small Portfolio
N/A
N/A
0%

48  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
Equity-Related
PIMCO Dividend and Income
Exposure to RAE Income Global Portfolio in
Equity Sleeve; remainder of portfolio invests in
fixed income instruments of varying maturities
N/A
No Limitation
No Limitation
PIMCO RAE PLUS EMG
Exposure to RAE Emerging Markets Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO StocksPLUS® International
(Unhedged)
Non-U.S. equity derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS® International
(U.S. Dollar-Hedged)
Non-U.S. equity derivatives (hedged to
U.S. dollars) backed by a portfolio of fixed
income instruments.
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO RAE PLUS International
Exposure to RAE International Large Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE Worldwide Long/Short PLUS
Long exposure to RAE Low Volatility U.S. Model
Portfolio, RAE Low Volatility Intl Model Portfolio
and RAE Low Volatility EMG Model Portfolio,
short exposure to certain traditional
capitalization-weighted equity indexes,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE Emerging Markets
Exposure to RAE Emerging Markets Portfolio
N/A
N/A
No Limitation
PIMCO RAE International
Exposure to RAE International Portfolio
N/A
N/A
No Limitation
U.S. Government
Securities
PIMCO Government Money Market
U.S. government securities
≤ 60 days
dollar-weighted
average maturity
Min 97% of total
assets Prime 1; ≤ 3%
of total assets Prime 2
0%
Short Strategy
PIMCO StocksPLUS® Short
Short S&P 500 Index derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(17)
1
As rated by Moody's, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality.
2
Certain Underlying PIMCO Funds may invest beyond these limits in U.S. dollar-denominated instruments of non-U.S. issuers.
3
Such limitation shall not apply to the Fund's investments in mortgage- and asset-backed securities.
4
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 10% of its total assets.
5
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
6
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund. Information for the PIMCO Low Duration Credit Fund is effective as of May 3, 2021.
7
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 5% of its total assets.
8
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index.
9
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML Developed Markets High Yield Constrained (USD Hedged) Index.
10
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to within 10% (plus or minus) of the Fund's benchmark's foreign currency exposure.
11
The Fund may also invest up to an additional 5% of its total assets in mortgage-related high yield instruments rated below Baa.
12
Such limitation shall not apply to the Fund's investments in mortgage-related securities.
13
Within such limitation, the Fund may invest in mortgage-related securities rated below B.
14
The percentage limitation relates to Fixed Income Instruments of non-U.S. issuers denominated in any currency.
15
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or in Fixed Income Instruments denominated in the currencies of, emerging market countries, and in short-term investments.
16
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or Fixed Income Instruments denominated in the currencies of, emerging market countries and in Fixed Income Instruments, each of which may be represented by forwards or derivatives such as options, futures contracts or swap agreements.
17
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
18
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 25% of its total assets.
19
With respect to the Fund's fixed income investments, the Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
20
The Bloomberg Barclays Long-Term Government/Credit Index is an unmanaged index of U.S. Government or investment grade credit securities having a maturity of 10 years or more.

April 30, 2021 | PROSPECTUS  49

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Global Diversified Allocation Portfolio (Consolidated)
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$11.30
$0.29
$0.04
$0.33
$(0.32)
$(0.76)
$0.00
$(1.08)
12/31/2019
9.53
0.32
1.73
2.05
(0.28)
0.00
0.00
(0.28)
12/31/2018
10.92
0.27
(1.24)
(0.97)
(0.20)
(0.22)
0.00
(0.42)
12/31/2017
9.61
0.29
1.32
1.61
(0.30)
0.00
0.00
(0.30)
12/31/2016
9.09
0.15
0.54
0.69
(0.14)
(0.02)
(0.01)
(0.17)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratios shown do not include expenses of the investment companies in which the Portfolio may invest. See the Fees and Expenses note in the Notes to Financial Statements for more information regarding the expenses and any applicable fee waivers associated with these investments.

50  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets(d)
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.55
3.99%
$218,035
0.57%
1.10%
0.57%
1.10%
2.76%
23%
11.30
21.61
218,006
0.57
1.10
0.57
1.10
2.97
19
9.53
(9.06)
163,649
0.57
1.10
0.57
1.10
2.49
16
10.92
16.86
151,288
0.57
1.10
0.57
1.10
2.77
2
9.61
7.64
109,396
0.56
1.10
0.56
1.10
1.67
22

April 30, 2021 | PROSPECTUS  51

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2082S_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
ACTIVE ASSET ALLOCATION PORTFOLIO – TOTAL RETURN ORIENTED
PIMCO Global Managed Asset Allocation Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Global Managed Asset Allocation Portfolio

Investment Objective
The Portfolio seeks total return which exceeds that of a blend of 60% MSCI World Index/40% Bloomberg Barclays U.S. Aggregate Index.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.95%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses
0.02%
Acquired Fund Fees and Expenses
0.22%
Total Annual Portfolio Operating Expenses(1)
1.34%
Fee Waiver and/or Expense Reimbursement(2)(3)
(0.20%)
Total Annual Portfolio Operating Expenses After Fee Waiver
and/or Expense Reimbursement(4)
1.14%
1
Total Annual Portfolio Operating Expenses do not match the Ratio of Expenses to Average Net Assets Excluding Waivers of the Portfolio, as set forth in the Financial Highlights table of the Portfolio’s prospectus, because the Ratio of Expenses to Average Net Assets Excluding Waivers reflects the operating expenses of the Portfolio and does not include Acquired Fund Fees and Expenses.
2
Pacific Investment Management Company LLC (“PIMCO”) has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the expenses attributable to the Management Fees of Underlying PIMCO Funds indirectly incurred by the Portfolio in connection with its investments in Underlying PIMCO Funds, to the extent the Portfolio’s Management Fees are greater than or equal to the Management Fees of the Underlying PIMCO Funds. This waiver renews annually for a full year unless terminated by PIMCO upon at least 30 days’ notice prior to the end of the contract term. For purposes of the expense reduction described above, references to Underlying PIMCO Funds include funds of PIMCO ETF Trust.
3
PIMCO has contractually agreed to waive the Portfolio’s advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Portfolio II Ltd. (the “GMAA Subsidiary”) to PIMCO. The GMAA Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO’s contract with the GMAA Subsidiary is in place.
4
“Other Expenses” and Acquired Fund Fees and Expenses include interest expense of the Portfolio and of the Underlying PIMCO Funds of 0.02% and 0.02%, respectively. Interest expense is borne by the Portfolio and the Underlying PIMCO Funds separately from the management fees paid to PIMCO. Excluding interest expense of the Portfolio and of the Underlying PIMCO Funds, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 1.10% for Administrative Class shares.
Example. The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$116
$405
$715
$1,595
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 360% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio is intended for investors who prefer to have their asset allocation decisions made by professional investment managers. PIMCO uses a three-step approach in seeking to achieve the Portfolio’s investment objective which consists of 1) developing a target asset allocation; 2) developing a series of relative value strategies designed to add value beyond the target allocation; and 3) utilizing hedging techniques to manage risks. PIMCO evaluates these three steps and uses varying combinations of Acquired Funds and/or direct investments to implement them within the Portfolio. The Portfolio may invest in Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end investment companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management (“Underlying PIMCO Funds”), and may also invest in other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds (collectively, “Acquired Funds”).
The Portfolio seeks to achieve its investment objective by investing under normal circumstances in a combination of affiliated and unaffiliated funds, which may or may not be registered under the Investment Company Act of 1940, as amended (the “1940 Act”), Fixed Income Instruments, equity securities, forwards and derivatives. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio will invest in Acquired Funds, securities, instruments and other investments to the extent permitted under the 1940 Act, or any exemptive relief therefrom. To the extent the Portfolio invests in Underlying PIMCO Funds, PIMCO expects to select such Underlying PIMCO Funds without considering or canvassing the universe of available unaffiliated Acquired Funds. The Portfolio will

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

invest either directly or indirectly (through a fund) in instruments that are economically tied to at least three countries (one of which may be the United States).
The Portfolio seeks concurrent exposure to a broad spectrum of asset classes and other investments. The Portfolio will typically invest 50% to 70%, and under normal circumstances will invest a minimum of 20%, of its net assets in equity-related investments (including investment in common stock, preferred securities, equity securities of real estate investment trusts and/or investment in the Domestic Equity-Related Underlying PIMCO Funds, the International Equity-Related Underlying PIMCO Funds and the PIMCO RealEstateRealReturn Strategy Fund, an Underlying PIMCO Fund and in other equity-related Acquired Funds). The Portfolio may invest up to 5% of its net assets in real estate investment trusts. With respect to its direct or indirect (through a fund) investments in equity securities, there is no limitation on the market capitalization range of the issuers in which the Portfolio may invest. The Portfolio may invest up to 5% of its net assets in commodity-related investments (including exposure to commodity-related investments obtained through investment in the PIMCO Cayman Commodity Portfolio II Ltd., a wholly-owned subsidiary of the Portfolio organized under the laws of the Cayman Islands (the “GMAA Subsidiary”), and investment in the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, Underlying PIMCO Funds). The GMAA Subsidiary is advised by PIMCO and primarily invests in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments. As discussed in greater detail elsewhere in this prospectus, the GMAA Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. The Portfolio may invest up to 25% of its total assets in the GMAA Subsidiary. The Portfolio may invest up to 10% of its net assets in equity securities that are economically tied to emerging market countries. The Portfolio’s combined investments in equity securities tied to emerging market countries, commodity-related investments and real estate investment trusts will normally not exceed 15% of its net assets.
The Portfolio may invest up to 30% of its total assets in Fixed Income Instruments denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 15% of its total assets in Fixed Income Instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other Fixed Income Instruments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The average portfolio duration of this Portfolio normally varies from 0-6 years. Duration is a measure used to
determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio may purchase and sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales.
The Portfolio’s assets are not allocated according to a predetermined blend of shares of the Acquired Funds and/or direct investments in securities, instruments and other investments. Instead, when making allocation decisions among the Acquired Funds, securities, instruments and other investments, PIMCO considers various qualitative and quantitative factors relating to the U.S. and non-U.S. economies, and securities and commodities markets. These factors include projected growth trends in the U.S. and non-U.S. economies, forecasts for interest rates and the relationship between short- and long-term interest rates (yield curve), current and projected trends in inflation, relative valuation levels in the equity, fixed income, commodity and real estate markets and various segments within those markets, the outlook and projected growth of various industrial sectors, information relating to business cycles, borrowing needs and the cost of capital, political trends data relating to trade balances, and labor information. PIMCO uses these factors to help determine the Portfolio’s target asset allocation and to identify potentially attractive relative value and risk hedging strategies. PIMCO has the flexibility to reallocate the Portfolio’s assets among any or all of the investment exposures represented by affiliated or unaffiliated funds, or invest directly in securities, instruments and other investments, based on its ongoing analyses of the global economy and financial markets. While these analyses are performed daily, material shifts in investment exposures typically take place over longer periods of time.
As part of its investment process, PIMCO will seek to reduce exposure to certain risks by implementing various hedging transactions.
Once the target asset allocation, relative value strategies and risk hedging strategies have been determined, PIMCO then evaluates various combinations of affiliated or unaffiliated funds, securities, instruments and other investments to obtain the desired exposures and invests accordingly.
Additional information for these Underlying PIMCO Funds can be found in the Statement of Additional Information and the Underlying PIMCO Funds’ prospectuses and financial reports. Additional Underlying PIMCO Funds may be added or deleted in the future without shareholder notification.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio include risks from direct investments and/ or indirect exposure through investment in Acquired Funds. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are:
Allocation Risk:the risk that a Portfolio could lose money as a result of less than optimal or poor asset allocation decisions. The Portfolio could miss attractive investment opportunities by underweighting

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PIMCO Global Managed Asset Allocation Portfolio

markets that subsequently experience significant returns and could lose value by overweighting markets that subsequently experience significant declines
Acquired Fund Risk:the risk that a Portfolio's performance is closely related to the risks associated with the securities and other investments held by the Acquired Funds and that the ability of a Portfolio to achieve its investment objective will depend upon the ability of the Acquired Funds to achieve their investment objectives
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Distressed Company Risk:the risk that securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the
lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Commodity Risk:the risk that investing in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Real Estate Risk:the risk that the Portfolio’s investments in Real Estate Investment Trusts (“REITs”) or real estate-linked derivative instruments will subject the Portfolio to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. A Portfolio’s investments in REITs or real estate-linked derivative instruments subject it to management and tax risks. In addition, privately traded REITs subject a Portfolio to liquidity and valuation risk
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Smaller Company Risk:the risk that the value of securities issued by a smaller company may go up or down, sometimes rapidly and unpredictably as compared to more widely held securities, due to narrow markets and limited resources of smaller companies. A Portfolio’s investments in smaller companies subject it to greater levels of credit, market and issuer risk
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Tax Risk:the risk that the tax treatment of swap agreements and other derivative instruments, such as commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures, may be affected by future regulatory or legislative changes that could affect whether income from such investments is “qualifying income” under Subchapter M of the Internal Revenue Code, or otherwise affect the character, timing and/or amount of the Portfolio’s taxable income or gains and distributions
Subsidiary Risk:the risk that, by investing in the GMAA Subsidiary, the Portfolio is indirectly exposed to the risks associated with the GMAA Subsidiary’s investments. The GMAA Subsidiary is not registered under the 1940 Act and may not be subject to all the investor protections of the 1940 Act. There is no guarantee that the investment objective of the GMAA Subsidiary will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Value Investing Risk:a value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
Exchange-Traded Fund Risk:the risk that an exchange-traded fund may not track the performance of the index it is designed to track, among other reasons, because of exchange rules, market prices of shares of an exchange-traded fund may fluctuate rapidly and materially, or shares of an exchange-traded fund may trade significantly above or below net asset value, any of which may cause losses to the Portfolio invested in the exchange-traded fund
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

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PIMCO Global Managed Asset Allocation Portfolio

Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The 60% MSCI World Index/40% Bloomberg Barclays U.S. Aggregate Index is a blended index. The MSCI World Index is a free float-adjusted market capitalization weighted index that is designed to measure the equity market performance of developed markets. The MSCI World Index consists of 23 developed market country indices. The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable, and dollar denominated. The Bloomberg Barclays U.S. Aggregate Index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
June 30, 2020
15.79%
Worst Quarter
March 31, 2020
-13.99%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Administrative Class Return
16.83%
8.94%
4.69%
60% MSCI World Index/40% Bloomberg Barclays
U.S. Aggregate Index (reflects no deductions for fees,
expenses or taxes)
13.31%
9.34%
7.68%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Erin Browne, Geraldine Sundstrom and Emmanuel Sharef. Ms. Browne is a Managing Director of PIMCO and a senior portfolio manager in the Asset Allocation team and has managed the Portfolio since January 2019. Ms. Sundstrom is a Managing Director of PIMCO and a senior portfolio manager in the Asset Allocation team and has managed the Portfolio since July 2015. Dr. Sharef is an Executive Vice President of PIMCO and has managed the Portfolio since December 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

5  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
As the Portfolio may invest in shares of Acquired Funds, including the Underlying PIMCO Funds, the risks of investing in the Portfolio may be closely related to the risks associated with the Acquired Funds, including Underlying PIMCO Funds, and their investments. However, as the Portfolio may also invest its assets directly in stocks or bonds of other issuers and in other instruments, such as forwards, options, futures contracts or swap agreements, the Portfolio may be directly exposed to certain risks described below. As such, unless stated otherwise, any reference in this section to “Portfolios” includes both the Portfolio and Acquired Funds. Where necessary in this section, the Portfolio is specifically referred to as the “Portfolio.”
Allocation Risk
The Portfolio’s investment performance depends upon how its assets are allocated and reallocated according to the Portfolio’s asset allocation targets and ranges. A principal risk of investing in the Portfolio is that PIMCO will make less than optimal or poor asset allocation decisions. PIMCO attempts to identify investment allocations that will provide consistent, quality performance for the Portfolio, but there is no guarantee that such allocation techniques will produce the desired results. It is possible that PIMCO will focus on an investment that performs poorly or underperforms other investments under various market conditions. You could lose money on your investment in the Portfolio as a result of these allocation decisions.
Acquired Fund Risk
Because the Portfolio may invest its assets in Acquired Funds, the risks associated with investing in the Portfolio may be closely related to the risks associated with the securities and other investments held by the Acquired Funds. The ability of the Portfolio to achieve its investment objective may depend upon the ability of the Acquired Funds to achieve their respective investment objectives. There can be no assurance that the investment objective of any Acquired Fund will be achieved.
The Portfolio’s net asset value (“NAV”) will fluctuate in response to changes in the NAVs of the Acquired Funds in which it invests. The extent to which the investment performance and risks associated with the Portfolio correlates to those of a particular Acquired Fund will depend upon the extent to which the Portfolio’s assets are allocated from time to time for investment in the Acquired Fund, which may vary. As discussed under “Description of Principal Risks—Market Risk,” because the NAV of the Portfolio is related to the NAVs of the Acquired Funds in which it invests, inaccuracies, delays or other disruptions in the calculation of an Acquired Fund’s NAV may adversely impact the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the NAV of the Portfolio’s shares.

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Prospectus

A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the

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PIMCO Variable Insurance Trust

Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Distressed Company Risk
The Portfolio’s investments in securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments. Issuers of distressed company securities may also be involved in restructurings or bankruptcy proceedings that may not be successful. An economic downturn or period of rising interest rates could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities (liquidity risk). If the issuer of a debt security is in default with respect to interest or principal payments, the Portfolio may lose its entire investment.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.

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Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio and certain Acquired Funds may rely on various third-party sources to calculate its NAV. As a result, the Portfolio and such Acquired Funds are subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s and Acquired Funds' calculations of their NAVs, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. Also, because the NAV of the Portfolio is related to the NAVs of the Acquired Funds in which it invests, the Portfolio may be adversely impacted by such inaccuracies, delays or other disruptions in the calculation of an Acquired Fund's NAV. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate,

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credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests. These factors include the possibility that the Portfolio's commodity derivatives positions may have different roll dates, reset dates or contract months than those specified in a particular commodity index.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio

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to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Commodity Risk
The Portfolio’s investments in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments. The GMAA Subsidiary and certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, may each concentrate its assets in a particular sector of the commodities market (such as oil, metal or agricultural products). As a result, the GMAA Subsidiary and certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, and, to the extent the Portfolio invests in the GMAA Subsidiary and/or certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, the Portfolio may be more susceptible to risks associated with those sectors. The prices for commodities in those sectors may fluctuate widely due to factors such as changes in value, supply and demand and governmental regulatory policies.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets

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in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Real Estate Risk
Investments in real estate investment trusts (“REITs”) or real estate-linked derivative instruments are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. An investment in a REIT or a real estate-linked derivative instrument that is linked to the value of a REIT is subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (the “Code”). In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. Finally, private REITs are not traded on a national securities exchange. As such, these products are generally illiquid. This reduces the ability of a Portfolio to redeem its investment early. Private REITs are also generally harder to value and may bear higher fees than public REITs.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leverage risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The GMAA Subsidiary will comply with these asset segregation or “earmarking” requirements to the same extent as the Portfolio. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy its obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities (or the value of the Acquired Funds). Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Smaller Company Risk
The general risks associated with fixed income securities and equity securities are particularly pronounced for securities issued by companies with smaller market capitalizations. These companies may have limited product lines, markets or financial resources or they may depend on a few key employees. As a result, they may be subject to greater levels of credit, market and issuer risk. Securities of smaller companies may trade less frequently and in lesser volumes than more widely held securities and their values may fluctuate more sharply than other securities. Companies with medium-sized market capitalizations may have risks similar to those of smaller companies.
Management Risk
The Portfolio, the GMAA Subsidiary and certain Acquired Funds are subject to management risk because they are actively managed investment portfolios. PIMCO or the sub-adviser, as applicable, or in the case of a fund that is not managed by PIMCO, such other fund’s investment adviser and sub-adviser, as applicable, and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, the GMAA Subsidiary and the Acquired Funds, as applicable, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio or an Acquired Fund seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio or Acquired Fund. To the extent the Portfolio or Acquired Fund employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio or Acquired Fund. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in

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value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Because a number of Underlying PIMCO Funds obtain exposure to certain proprietary model stock portfolios by investing in equity total return swaps based on such model portfolios, in other securities and instruments to replicate the performance of such model portfolios, or directly in the equity securities held in such model portfolios, such Underlying PIMCO Funds will be subject to the risks associated with the management of these proprietary model stock portfolios by the sub-adviser to such Underlying PIMCO Funds.
Tax Risk
The Portfolio and certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, gain exposure to the commodities markets through investments in commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures. The Portfolio may also gain exposure indirectly to commodity markets by investing in the GMAA Subsidiary, which invests primarily in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and/or other Fixed Income Instruments. In order for the Portfolio to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”), the Portfolio must derive at least 90 percent of its gross income each taxable year from certain qualifying sources of income.
As more fully described below under “Tax Consequences-A Note on the Portfolio,” the Internal Revenue Service (the “IRS”) issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. The IRS has issued private letter rulings in which the IRS specifically concluded that income derived from an investment in a subsidiary will also constitute qualifying income to the Portfolio. Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio‘s income from an investment in the subsidiary distributed annually or is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the Investment Company Act of 1940, as amended (the “1940 Act”).
The Portfolio will seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the GMAA Subsidiary. If the IRS were to determine that income derived from certain commodity-linked notes or from investments in the GMAA Subsidiary does not constitute qualifying income, the Portfolio and certain Underlying PIMCO Funds, including the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, might be adversely affected and would be required to reduce their exposure to such investments which might result in difficulty in implementing their investment strategies and increased costs and taxes.
The use of commodity index-linked notes and investments in the GMAA Subsidiary involve specific risks. See “Characteristics and Risks of Securities and Investment Techniques-Derivatives-A Note on the Portfolio” below for further information regarding commodity index-linked notes, including the risks associated with these instruments. In addition, see “Characteristics and Risks of Securities and Investment Techniques-Investments in the Wholly-Owned Subsidiary” below for further information regarding the GMAA Subsidiary, including the risks associated with investing in the GMAA Subsidiary.
Subsidiary Risk
By investing in the GMAA Subsidiary, the Portfolio is indirectly exposed to the risks associated with the GMAA Subsidiary’s investments. The investments held by the GMAA Subsidiary are generally similar to those that are permitted to be held by the Portfolio and are subject to the same risks that apply to similar investments if held directly by the Portfolio. These risks are described elsewhere in this prospectus. There can be no assurance that the investment objective of the Portfolio or the GMAA Subsidiary will be achieved.
The GMAA Subsidiary is not registered under the 1940 Act, and, unless otherwise noted in this prospectus, is not subject to all the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the GMAA Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the GMAA Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Value Investing Risk
Value investing attempts to identify companies that are believed to be undervalued. Value stocks typically have prices that are low relative to factors such as the company’s earnings, cash flow or dividends. A value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur. A value investing style may perform better or worse than equity portfolios that focus on growth stocks or that have a broader investment style.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.
Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
Exchange-Traded Fund (“ETF”) Risk
Investments in ETFs entail certain risks. Investments in ETFs designed to track an index involve the risk that the ETF’s performance may not track the performance of the index the ETF is designed to track. This deviation may occur due to cash inflows and outflows from and to investors buying and redeeming shares or due to occasional differences between the composition of the index and the securities held by the ETF. In addition, investments in ETFs involve the risk that the market prices of ETF shares will fluctuate, sometimes rapidly and materially, in response to changes in the ETF’s NAV, the value of ETF holdings and supply and demand for ETF shares. Although ETFs will generally trade close to NAV, market volatility, lack of an active trading market for ETF shares, disruptions at market participants (such as Authorized Participants or market makers) and any disruptions in the ordinary functioning of the creation/redemption process may result in ETF shares trading significantly above (at a “premium”) or below (at a “discount”) NAV. Significant losses may result when transacting in ETF shares in these and other circumstances.

April 30, 2021 | PROSPECTUS  15

PIMCO Variable Insurance Trust

LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters. PIMCO also serves as the investment adviser for the GMAA Subsidiary.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.95% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.90% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
As discussed in the “Portfolio Summary-Principal Investment Strategies” section, the Portfolio may pursue its investment objective by investing in the GMAA Subsidiary. The GMAA Subsidiary has entered into a separate contract with PIMCO whereby PIMCO provides investment advisory and other services to the GMAA Subsidiary. In consideration of these services, the GMAA Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. PIMCO has contractually agreed to waive the advisory fee and the supervisory and administrative fee it receives from the Portfolio in an amount equal to the management fee and administrative services fee, respectively, paid to PIMCO by the GMAA Subsidiary. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO’s contract with the GMAA Subsidiary is in place.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees at the annual rate of 0.05% for
Administrative Class shares (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not:

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Fund of Funds Fees
The Portfolio is permitted to invest in Underlying PIMCO Funds, which, for the Portfolio, is defined to include Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. The Portfolio is further permitted to invest in Acquired Funds, which, for the Portfolio, is defined to include the Underlying PIMCO Funds and other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds, which may or may not be registered under the 1940 Act.
The Portfolio pays advisory and supervisory and administrative fees directly to PIMCO at an annual rate stated above, based on the average daily net assets attributable in the aggregate to the Portfolio’s Administrative Class shares. The Portfolio also indirectly pays its proportionate share of the advisory, supervisory and administrative and management fees charged by PIMCO to the Underlying PIMCO Funds and, to the extent not included among the Underlying PIMCO Funds, funds of PIMCO ETF Trust in which the Portfolio invests (collectively, “Underlying PIMCO Fund Fees”).
PIMCO has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, to the extent necessary, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the Underlying PIMCO Fund Fees indirectly incurred by the Portfolio in connection with its investments in Underlying PIMCO Funds (for purposes of this expense reduction, this term includes funds of PIMCO ETF Trust), to the extent the Portfolio’s advisory fee or advisory fee and supervisory and administrative fee, taken together, are greater than or equal to the Underlying PIMCO Fund Fees. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term.
The Acquired Fund Fees and Expenses shown in the Annual Portfolio Operating Expenses table may be higher than the Underlying PIMCO Fund Fees used for purposes of the Expense Reduction shown in that table due to differences in the methods of calculation. The Acquired Fund Fees and Expenses, as required to be shown in the Annual Portfolio Operating Expenses table, are calculated using the total operating expenses for each Underlying PIMCO Fund (and any unaffiliated funds) over the Portfolio’s average net assets. The Underlying PIMCO Fund Fees that are used for purposes of implementing the expense reduction described above are calculated using the advisory and supervisory and administrative fees for each Underlying PIMCO Fund over the total assets invested in Underlying PIMCO Funds. Thus, the Acquired Fund Fees and Expenses listed in the Annual Portfolio Operating Expenses table will typically be higher than the Underlying PIMCO Fund Fees used to calculate the Expense Reduction when the Portfolio employs leverage as an investment strategy.
The expenses associated with investing in a fund of funds are generally higher than those for mutual funds that do not invest in other funds. The cost of investing in the Portfolio will generally be higher than the cost of investing in a Portfolio that invests directly in individual stocks and bonds. By investing in the Portfolio, an investor will indirectly bear fees and expenses charged by non-PIMCO Acquired Funds (and may indirectly bear a portion of the fees and expenses charged by Underlying PIMCO Funds to the extent such fees and expenses are not waived or reimbursed pursuant to applicable waiver and reimbursement agreements) in addition to the Portfolio’s direct fees and expenses. In addition, the use of a fund of funds structure could affect the timing, amount and character of distributions to shareholders and may therefore increase the amount of taxes payable by shareholders. The Portfolio, to the extent it invests in Underlying PIMCO Funds, invests in Institutional Class or Class M shares of the Underlying PIMCO Funds, which are not subject to any sales charges or distribution (12b-1) fees.
The following table summarizes the annual expenses borne by Institutional Class or Class M shareholders of the Underlying PIMCO Funds (or, in the case of those operating as exchange-traded funds, the Underlying PIMCO Fund shareholders). Because the Portfolio, to the extent it invests in Underlying PIMCO Funds, invests in Institutional Class or Class M shares of the Underlying PIMCO Funds, shareholders of the Portfolio would indirectly bear a proportionate share of these expenses, depending upon how the Portfolio’s assets are allocated from time to time among the Underlying PIMCO Funds.
For a complete description of an Underlying PIMCO Fund, please see the Underlying PIMCO Fund’s prospectus or offering memorandum, as applicable. For a summary description of the Underlying PIMCO Funds, please see the “Descriptions of the Underlying PIMCO Funds” section in this prospectus.
Annual Underlying PIMCO Fund Expenses
(Based on the average daily net assets attributable to an Underlying PIMCO Fund’s Institutional Class shares (or Class M shares in the case of the PIMCO Government Money Market Fund )).

April 30, 2021 | PROSPECTUS  19

PIMCO Variable Insurance Trust

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO California Intermediate Municipal Bond Fund
0.445%
0.00%
0.445%
PIMCO California Municipal Bond Fund
0.44%
0.02%
0.46%
PIMCO California Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Climate Bond Fund
0.50%
0.00%
0.50%
PIMCO CommoditiesPLUS® Strategy Fund
0.74%
0.27%
1.01%(3)
PIMCO CommodityRealReturn Strategy Fund®
0.74%
0.76%
1.50%(4)
PIMCO Credit Opportunities Bond Fund
0.90%
0.02%
0.92%
PIMCO Diversified Income Fund
0.75%
0.04%
0.79%
PIMCO Dividend and Income Fund
0.75%
0.05%
0.80%(5)
PIMCO Dynamic Bond Fund
0.80%
0.05%
0.85%
PIMCO Emerging Markets Bond Fund
0.83%
0.05%
0.88%
PIMCO Emerging Markets Corporate Bond Fund
0.90%
0.12%
1.02%
PIMCO Emerging Markets Currency and Short-Term Investments Fund
0.85%
0.03%
0.88%
PIMCO Emerging Markets Local Currency and Bond Fund
0.90%
0.80%
1.70%
PIMCO ESG Income Fund
0.50%
0.07%
0.57%(6)
PIMCO Extended Duration Fund
0.50%
1.21%
1.71%
PIMCO Global Advantage® Strategy Bond Fund
0.65%
0.21%
0.86%
PIMCO Global Bond Opportunities Fund (U.S. Dollar-Hedged)
0.55%
0.04%
0.59%
PIMCO Global Bond Opportunities Fund (Unhedged)
0.55%
0.12%
0.67%
PIMCO GNMA and Government Securities Fund
0.50%
0.33%
0.83%
PIMCO Government Money Market Fund
0.18%
0.00%
0.18%(7)
PIMCO High Yield Fund
0.55%
0.02%
0.57%
PIMCO High Yield Municipal Bond Fund
0.55%
0.08%
0.63%
PIMCO High Yield Spectrum Fund
0.60%
0.02%
0.62%
PIMCO Income Fund
0.50%
0.59%
1.09%
PIMCO International Bond Fund (U.S. Dollar-Hedged)
0.50%
0.10%
0.60%
PIMCO International Bond Fund (Unhedged)
0.50%
0.13%
0.63%
PIMCO Investment Grade Credit Bond Fund
0.50%
0.35%
0.85%
PIMCO Long Duration Total Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term Credit Bond Fund
0.55%
0.29%
0.84%
PIMCO Long-Term Real Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term U.S. Government Fund
0.475%
1.38%
1.855%
PIMCO Low Duration Credit Fund(8)
0.70%
0.05%
0.75%
PIMCO Low Duration ESG Fund
0.50%
0.08%
0.58%
PIMCO Low Duration Fund
0.46%
0.41%
0.87%
PIMCO Low Duration Fund II
0.50%
0.03%
0.53%
PIMCO Low Duration Income Fund
0.50%
0.05%
0.55%
PIMCO Moderate Duration Fund
0.46%
0.15%
0.61%
PIMCO Mortgage Opportunities and Bond Fund
0.60%
1.22%
1.82%
PIMCO Mortgage-Backed Securities Fund
0.50%
0.25%
0.75%
PIMCO Municipal Bond Fund
0.44%
0.07%
0.51%
PIMCO National Intermediate Municipal Bond Fund
0.45%
0.00%
0.45%
PIMCO New York Municipal Bond Fund
0.445%
0.05%
0.495%
PIMCO Preferred and Capital Securities Fund
0.79%
0.09%
0.88%(9)
PIMCO RAE Emerging Markets Fund
0.75%
0.02%
0.77%(10)
PIMCO RAE Fundamental Advantage PLUS Fund
0.89%
0.07%
0.96%
PIMCO RAE International Fund
0.50%
0.02%
0.52%(5)
PIMCO RAE PLUS EMG Fund
1.10%
0.21%
1.31%
PIMCO RAE PLUS Fund
0.79%
0.08%
0.87%
PIMCO RAE PLUS International Fund
0.82%
0.05%
0.87%
PIMCO RAE PLUS Small Fund
0.84%
0.09%
0.93%
PIMCO RAE US Fund
0.40%
0.02%
0.42%(5)

20  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO RAE US Small Fund
0.50%
0.04%
0.54%
PIMCO RAE Worldwide Long/Short PLUS Fund
1.19%
0.09%
1.28%
PIMCO Real Return Fund
0.45%
0.08%
0.53%
PIMCO RealEstateRealReturn Strategy Fund
0.74%
1.36%
2.10%
PIMCO Short Asset Investment Fund
0.34%
0.02%
0.36%
PIMCO Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Short-Term Fund
0.45%
0.10%
0.55%
PIMCO StocksPLUS® Absolute Return Fund
0.64%
0.08%
0.72%
PIMCO StocksPLUS® Fund
0.50%
0.06%
0.56%
PIMCO StocksPLUS® International Fund (U.S. Dollar-Hedged)
0.75%
0.25%
1.00%
PIMCO StocksPLUS® International Fund (Unhedged)
0.64%
0.38%
1.02%
PIMCO StocksPLUS® Long Duration Fund
0.59%
0.42%
1.01%
PIMCO StocksPLUS® Short Fund
0.64%
0.45%
1.09%
PIMCO StocksPLUS® Small Fund
0.69%
0.06%
0.75%
PIMCO Strategic Bond Fund
0.55%
0.02%
0.57%(11)
PIMCO Total Return ESG Fund
0.50%
0.46%
0.96%
PIMCO Total Return Fund
0.46%
0.24%
0.70%
PIMCO Total Return Fund II
0.50%
0.26%
0.76%
PIMCO Total Return Fund IV
0.50%
0.30%
0.80%
PIMCO TRENDS Managed Futures Strategy Fund
1.40%
0.29%
1.69%(12)
1
“Management Fees” reflects an advisory fee and a supervisory and administrative fee payable by an Underlying PIMCO Fund to PIMCO.
2
Other Expenses include expenses such as organizational expenses, interest expense, taxes, governmental fees, pro rata Trustees' fees and acquired fund fees and expenses attributable to the Institutional Class or Class M shares or the Fund in the case of exchange-traded funds of the PIMCO ETF Trust or PIMCO Equity Series.
3
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund III Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
4
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund I Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
5
PIMCO has contractually agreed, through October 31, 2021, to waive a portion of the Fund's supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund's organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Equity Series at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
6
PIMCO has contractually agreed, through July 31, 2022, to waive a portion of the Fund’s supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
7
To maintain certain net yields for the Fund, PIMCO or its affiliates may temporarily and voluntarily waive, reduce or reimburse all or any portion of the Fund's fees and expenses.
8
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund.
9
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Capital Securities Fund (Cayman) Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
10
PIMCO has contractually agreed, through July 31, 2022, to reduce its supervisory and administrative fee for each share class of the Fund by 0.05% of the average daily net assets attributable to the applicable class of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years from the date of waiver.
11
PIMCO has contractually agreed, through July 31, 2022, to reduce its advisory fee by 0.10% of the average daily net assets of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years.

April 30, 2021 | PROSPECTUS  21

PIMCO Variable Insurance Trust

12
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund VIII, Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
Individual Portfolio Managers
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Global Managed Asset Allocation
Erin Browne
1/19
Managing Director, PIMCO. Ms. Browne is a portfolio manager in the Newport Beach office,
focusing on multi-asset strategies. In her role, she works with PIMCO's asset allocation team
and with portfolio managers across asset classes and sectors globally. Prior to joining
PIMCO in 2018, Ms. Browne was a managing director and head of asset allocation at UBS
Asset Management, helping to drive the firm's macro research, capital market assumptions,
tactical asset allocation and strategic asset allocation views across asset classes. Previously,
she was head of macro investments at UBS O'Connor, a multi-strategy hedge fund manager,
and a global macro portfolio manager at Point72 Asset Management. Ms. Browne has also
held roles at Citigroup, Moore Capital Management and Neuberger Berman, and she began
her career at Lehman Brothers. She has investment experience since 2002 and holds a
bachelor's degree in economics from Georgetown University.
PIMCO Global Managed Asset Allocation
Emmanuel Sharef
12/19
Executive Vice President, PIMCO. Dr. Sharef is an executive vice president and portfolio
manager in the Newport Beach office, focused on asset allocation strategies and the
residential real estate market. He is a member of the Americas Portfolio Committee and has
served as a rotating member of the Investment Committee. Prior to joining PIMCO in 2011,
he worked in the mortgage credit strategists group at Morgan Stanley. He has investment
and financial services experience since 2008 and holds a Ph.D. in operations research from
Cornell University, specializing in statistics and biometrics. He received an undergraduate
degree from Princeton University.
PIMCO Global Managed Asset Allocation
Geraldine Sundstrom
7/15
Managing Director, PIMCO. Ms. Sundstrom is a portfolio manager in the London office,
focusing on asset allocation strategies. Prior to joining PIMCO in 2015, she was a partner
and portfolio manager at Brevan Howard, where she led the Emerging Markets Strategies
Fund. Previously, she was a portfolio manager at Moore Capital Management. She has
investment experience since 1996 and holds a master's degree in finance from Birkbeck
College at London University and two degrees from Universite Paris Dauphine.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

22  Prospectus | PIMCO Variable Insurance Trust

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PIMCO Variable Insurance Trust

Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the 1940 Act, an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

24  Prospectus | PIMCO Variable Insurance Trust

Prospectus

conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

April 30, 2021 | PROSPECTUS  25

PIMCO Variable Insurance Trust

fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

26  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

April 30, 2021 | PROSPECTUS  27

PIMCO Variable Insurance Trust

Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
A Note on the Portfolio. One of the requirements for favorable tax treatment as a regulated investment company under the Code is that the Portfolio derives at least 90% of its gross income from certain qualifying sources of income. The IRS has issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. As such, the Portfolio’s ability to utilize commodity-linked swaps as part of its investment strategy is limited to a maximum of 10% of its gross income.
However, in a subsequent revenue ruling, the IRS provides that income from alternative investment instruments (such as certain commodity index-linked notes) that create commodity exposure may be considered qualifying income under the Code. The IRS has also issued private letter rulings in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the

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“Notes Rulings”). In addition, the IRS has also issued private letter rulings in which the IRS specifically concluded that income derived from an investment in a subsidiary will also constitute qualifying income, even if that subsidiary itself owns commodity-linked swaps. The Portfolio will continue to seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the GMAA Subsidiary.
Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio‘s income from an investment in the subsidiary is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the 1940 Act. In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings. There can be no assurance that the IRS will not change its position with respect to some or all of these conclusions or that future legislation will not adversely impact the tax treatment of the Portfolio’s commodity-linked investments. If the IRS were to change or reverse its position, or if future legislation adversely affected the tax treatment of the Portfolio’s commodity-linked investments, there would likely be a significant adverse impact on the Portfolio, including the possibility of failing to qualify as a regulated investment company. If the Portfolio did not qualify as a regulated investment company for any taxable year, its taxable income would be subject to tax at the Portfolio level at regular corporate tax rates (without reduction for distributions to shareholders) and to a further tax at the shareholder level when such income is distributed. Furthermore, the tax treatment of commodity-linked notes, other commodity-linked derivatives, and the Portfolio’s investments in the GMAA Subsidiary may otherwise be adversely affected by future legislation, court decisions, Treasury Regulations and/or guidance issued by the IRS. Such developments could affect the character, timing and/or amount of the Portfolio’s taxable income or any distribution made by the Portfolio or result in the inability of the Portfolio to operate as described in this Prospectus.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
As the Portfolio may invest in shares of the Acquired Funds, the risks of investing in the Portfolio may be closely related to the risks associated with the Acquired Funds and their investments. However, as the Portfolio may also invest its assets directly in Fixed Income Instruments, equity securities, forwards or derivatives, such as options, futures contracts or swap agreements, other affiliated or unaffiliated funds, and other investments, the Portfolio may be directly exposed to certain risks described below.
This section provides additional information about some of the principal investments and related risks of the Portfolio and of certain Acquired Funds described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio and certain Acquired Funds from time to time. Generally, the characteristics and risks of securities and investment techniques that may be used by the Acquired Funds from time to time are similar to those described below. However, the risks associated with an Acquired Fund’s investments are described more fully in each Acquired Fund’s prospectus. Accordingly, please see an Acquired Fund’s prospectus for a more complete description of the Acquired Fund and the risks associated with its investments.
Most of these securities and investment techniques described herein are discretionary, which means that PIMCO, or in the case of a fund that is not managed by PIMCO, such fund’s investment adviser and sub-adviser, as applicable, can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio or Acquired Funds. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Because the Portfolio may invest a portion of its assets in the GMAA Subsidiary, which may hold some of the investments described in this prospectus, the Portfolio may be indirectly exposed to the risks associated with those investments. With respect to its investments, the GMAA Subsidiary will generally be subject to the same fundamental, non- fundamental and certain other investment restrictions as the Portfolio; however, the GMAA Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity- linked derivative instruments. The Portfolio and the GMAA Subsidiary may test for compliance with certain investment restrictions on a consolidated basis, except that with respect to their investments in certain securities that may involve leverage, the GMAA Subsidiary will comply with asset segregation or “earmarking” requirements to the same extent as the Portfolio.
Investors should be aware that the investments made by a Portfolio and the results achieved by a Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to a Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact a Portfolio’s portfolio management. For example, a Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to

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significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause Portfolios to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase a Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause a Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect a Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to
identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a

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portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government.
FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the

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principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage

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assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the
effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also

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will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate
instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation

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decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value
of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this Prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions. Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights. Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods

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of time. In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
While certain Underlying PIMCO Funds will generally invest in equity derivatives, each such Underlying PIMCO Fund may invest without limit directly in equity securities, including common stocks, preferred securities and convertible securities. In addition, the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, each an Underlying PIMCO Fund, may invest in equity securities of issuers in commodity-related industries, and the PIMCO RealEstateRealReturn Strategy Fund, an Underlying PIMCO Fund, may invest in REITs and equity securities of issuers in real estate-related industries. The Portfolio may also invest directly in equity securities. When investing directly in equity securities, the Portfolio will not be limited to only those equity securities with any particular weighting in the Portfolio’s benchmark index, if any. Generally, the Portfolio may consider investing directly in equity securities when derivatives on the underlying securities appear to be overvalued.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for

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Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market
country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small;

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differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging
transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.

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Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of
whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws,

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rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
A Note on the Portfolio. In light of relevant IRS guidance, as discussed above under “Tax Consequences—A Note on the Portfolio,” the Portfolio will seek to gain exposure to the commodity markets primarily through investments in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices, and through investments in the GMAA Subsidiary (as discussed below). The Portfolio may also invest in commodity-linked notes with principal and/or coupon payments linked to the value of particular commodities or commodity futures contracts, or a subset of commodities and commodities futures contracts. These notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the note. The value of these notes will rise or fall in response to changes in the underlying commodity, commodity futures contract, subset of commodities, subset of commodities futures contracts or commodity index.
These notes expose the Portfolio economically to movements in commodity prices. These notes also are subject to risks, such as credit, market and interest rate risks, that in general affect the values of debt securities. In addition, these notes are often leveraged, increasing the volatility of each note’s market value relative to changes in the

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Prospectus

underlying commodity, commodity futures contract or commodity index. Therefore, at the maturity of the note, the Portfolio may receive more or less principal than it originally invested. The Portfolio might receive interest payments on the note that are more or less than the stated coupon interest payments.
The Portfolio may also invest in other commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures. The value of a commodity-linked derivative investment generally is based upon the price movements of a physical commodity (such as energy, mineral, or agricultural products), a commodity futures contract, a subset of commodities, a subset of commodities futures contracts or commodity index, or other economic variable based upon changes in the value of commodities or the commodities markets.
Options transactions may be effected on exchanges or in the OTC market. When OTC options are purchased, the Portfolio’s portfolio bears the risk that the counterparty that wrote the option will be unable or unwilling to perform its obligations under the option contract. Options may also be illiquid and, in such cases, the Portfolio may have difficulty closing out its position. OTC options also may include options on baskets of specific securities.
Many swap transactions are privately negotiated agreements between the Portfolio and a counterparty to exchange or swap investment cash flows or assets at specified intervals in the future. The obligations may extend beyond one year. There is often no central exchange for swap transactions and therefore they can be less liquid investments than exchange-traded instruments. The Dodd-Frank Act and related regulatory developments require the clearing and exchange-trading of certain standardized OTC derivative instruments that the CFTC and SEC have defined as “swaps.” The CFTC has implemented mandatory exchange- trading and clearing requirements under the Dodd-Frank Act and the CFTC continues to approve contracts for central clearing. Uncleared swaps are subject to margin requirements that are being implemented on a phased-in basis. The investment adviser will continue to monitor these developments, particularly to the extent regulatory changes affect a Portfolio’s ability to enter into swap agreements.
As described below under “Characteristics and Risks of Securities and Investment Techniques—Investments in the Wholly-Owned Subsidiary,” the Portfolio may gain exposure to commodity markets by investing in the GMAA Subsidiary. It is expected that the GMAA Subsidiary will invest primarily in commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments.
The IRS issued a revenue ruling that limits the extent to which the Portfolio may invest directly in commodity-linked swaps or certain other commodity- linked derivatives. The GMAA Subsidiary, on the other hand, may invest in these commodity-linked derivatives generally without limitation. See “Tax Consequences—A Note on the Portfolio,” above for further information.
Investments in a Wholly Owned Subsidiary
Investments in the GMAA Subsidiary are expected to provide the Portfolio with exposure to the commodity markets within the limitations of Subchapter M of the Code and recent IRS revenue rulings, as discussed above under “Tax Consequences—A Note on the Portfolio.”
It is expected that the GMAA Subsidiary will invest primarily in commodity- linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation- indexed securities and other Fixed Income Instruments. Although the Portfolio may enter into these commodity-linked derivative instruments directly, the Portfolio will likely gain exposure to these derivative instruments indirectly by investing in the GMAA Subsidiary. To the extent that PIMCO believes that these commodity-linked derivative instruments are better suited to provide exposure to the commodities market than commodity index-linked notes, the Portfolio’s investment in the GMAA Subsidiary will likely increase. The GMAA Subsidiary will also invest in inflation-indexed securities and/or other Fixed Income Instruments, which are intended to serve as margin or collateral for the GMAA Subsidiary’s derivatives position, common and preferred securities as well as convertible securities of issuers in commodity-related industries, collateralized debt obligations, event-linked bonds and event-linked swaps. To the extent that the Portfolio invests in the GMAA Subsidiary, it may be subject to the risks associated with those derivative instruments and other securities, which are discussed elsewhere in this prospectus.
While the GMAA Subsidiary may be considered similar to an investment company, it is not registered under the 1940 Act and, unless otherwise noted in the prospectus, is not subject to all of the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the GMAA Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the GMAA Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.

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An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets
determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in Underlying PIMCO Funds and, to the extent permitted by the 1940 Act or exemptive relief therefrom, other affiliated and unaffiliated funds, which may or may not be registered under the 1940 Act, such as open-end or closed-end management investment companies, exchange-traded funds and exchange-traded vehicles. Other unaffiliated investment companies are not required to make their shares available for purchase by the Portfolio, and there is no guarantee that such investment will be, or will continue to be, available. Each Underlying PIMCO Fund may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The limitation described in the foregoing sentence shall not apply to the Portfolio’s investment in the GMAA Subsidiary. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the

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Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio and each Underlying PIMCO Fund may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act, and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no
added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a

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portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. In addition to indirectly bearing the expenses associated with portfolio turnover of the Acquired Funds, the Portfolio will directly bear these expenses to the extent that it invests in other securities and instruments.  Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objectives of the Portfolio and certain Underlying PIMCO Funds are non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval. The investment objectives of certain Underlying PIMCO Funds are fundamental and may not be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to
fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber

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security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, sub-advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Descriptions of the Underlying PIMCO Funds
The Portfolio may invest its assets in some or all of the Underlying PIMCO Funds, which for the Portfolio, is defined to include Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end investment companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. The Portfolio is further permitted to invest in Acquired Funds, which, for the Portfolio, is defined to include the Underlying PIMCO Funds and other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds, which may or may not be registered under the 1940 Act. Because the Underlying PIMCO Funds are not offered in this prospectus, the following provides a general description of the main investments and other information about the Underlying PIMCO Funds. At the discretion of PIMCO and without shareholder approval, the Portfolio may invest in additional Underlying PIMCO Funds created in the future. For a complete description of an Underlying PIMCO Fund, please see that Fund’s Institutional Class or Class M prospectus, which is incorporated herein by reference and is available free of charge by telephoning 1-800-927-4648.
Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Short Duration
PIMCO Low Duration Income
Short maturity fixed income instruments
0 to 3 years
Max 30% of total
assets below Baa(3)
No Limitation(4)
PIMCO Short Asset Investment
Money market instruments and short maturity
fixed income instruments
≤ 1.5 years
Baa to Aaa
0%
PIMCO Short-Term
Money market instruments and short maturity
fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below Baa
0-10% of total
assets(5)
PIMCO Low Duration
Short maturity fixed income instruments
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration II
Short maturity fixed income instruments with
quality and non-U.S. issuer restrictions
1 to 3 years
A to Aaa
0%
PIMCO Low Duration ESG
Short maturity fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration Credit(6)
Diversified portfolio of fixed income
instruments
0 to 3 years
Max 10% of total
assets below Caa
0-25% of total
assets(7)
Intermediate
Duration
PIMCO Moderate Duration
Short and intermediate maturity fixed income
instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO GNMA and Government
Securities
Short and intermediate maturity
mortgage-related fixed income securities issued
by the Government National Mortgage
Association and U.S. government securities
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa
0%
PIMCO High Yield
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(8) max
20% of total assets
Caa or below
0-20% of total
assets(5)
PIMCO High Yield Spectrum
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(9)
No Limitation(10)
PIMCO Mortgage-Backed Securities
Short and intermediate maturity
mortgage-related fixed income instruments
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa(11)
0%
PIMCO Total Return
Intermediate maturity fixed income instruments
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return II
Intermediate maturity fixed income instruments
with quality and non-U.S. issuer restrictions
+/-2 years of its
benchmark
Baa to Aaa
0%
PIMCO Total Return ESG
Intermediate maturity fixed income instruments
with prohibitions on firms engaged in socially
sensitive practices
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return IV
Intermediate maturity fixed income instruments
+/-1.5 years of its
benchmark
Baa to Aaa
0-15% of total
assets(7)
PIMCO Investment Grade Credit Bond
Investment grade fixed income securities
+/-2 years of its
benchmark
Max 15% of total
assets below Baa
0-30% of total
assets(5)

46  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Long Duration
PIMCO Long Duration Total Return
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Extended Duration
Long-term maturity fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO Long-Term U.S. Government
Long-term maturity fixed income securities
≥ 8 years
A to Aaa; max 25% Aa;
max 10% A
0%
PIMCO Mortgage Opportunities and
Bond
Mortgage-related assets and fixed income
instruments
(-1) to 8 years
Max 50% of total
assets below Baa(12)
0%
PIMCO Long-Term Credit Bond
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
B to Aaa; max 20% of
total assets below Baa
0-30% of total
assets(5)
Income
PIMCO ESG Income
Broad range of fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Income
Broad range of fixed income instruments
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Preferred and Capital Securities
Capital securities and preferred securities
+/-2 years of its
benchmark
No Limitation
No Limitation(4)
Inflation-Related
PIMCO Real Return
Inflation-indexed fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO Long-Term Real Return
Inflation-indexed fixed income securities
+/-4 years of its
benchmark
B to Aaa; max 20% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO CommoditiesPLUS® Strategy
Commodity-linked derivative instruments
backed by an actively managed low volatility
portfolio of fixed income instruments
≤ 1 year
Max 10% of total
assets below Baa
0-20%(4)
PIMCO CommodityRealReturn Strategy®
Commodity-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO RealEstateRealReturn Strategy
Real estate-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
Tax Exempt
PIMCO California Short Duration
Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal and California
income tax)
≤ 3 years
Caa to Aaa; max 10%
of total assets below
Baa
0%
PIMCO California Municipal Bond
Municipal securities (exempt from federal and
California income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO Short Duration Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal income tax)
≤ 3 years
Baa to Aaa
0%
PIMCO California Intermediate Municipal
Bond
Intermediate maturity municipal securities
(exempt from federal and California income
tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO National Intermediate Municipal
Bond
Municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO New York Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal and New York
income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO High Yield Municipal Bond
Intermediate to long-term maturity high yield
municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
No Limitation
0%

April 30, 2021 | PROSPECTUS  47

PIMCO Variable Insurance Trust

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
PIMCO Emerging Markets Bond
Emerging market fixed income instruments
+/- 2 years of its
benchmark
Max 15% of total
assets below B
≥ 80% of assets(14)
PIMCO Emerging Markets Currency and
Short-Term Investments
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and short-term investments
≤ 2 years
Max 15% of total
assets below B
No Limitation(15)
PIMCO International Bond
(U.S. Dollar-Hedged)
Intermediate maturity hedged non-U.S. fixed
income instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO International Bond (Unhedged)
Intermediate maturity non-U.S. fixed income
instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation
PIMCO Global Advantage® Strategy
Bond
U.S. and non-U.S. fixed income instruments
≤ 8 years
Max 15% of total
assets below B
No Limitation
PIMCO Global Bond Opportunities
(U.S. Dollar-Hedged)
U.S. and hedged non-U.S. intermediate maturity
fixed income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO Global Bond Opportunities
(Unhedged)
U.S. and non-U.S. intermediate maturity fixed
income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation
PIMCO Diversified Income
Investment grade corporate, high yield and
emerging market fixed income instruments
3 to 8 years
Max 10% below B
No Limitation
PIMCO Emerging Markets Local Currency
and Bond
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and fixed income instruments
+/-2 years of its
benchmark
Max 15% of total
assets below B
No Limitation(16)
PIMCO Emerging Markets Corporate
Bond
Diversified portfolio of fixed income
instruments economically tied to emerging
market countries
+/- 2 years of its
benchmark
Max 15% of total
assets below B
No Limitation
Absolute Return
PIMCO Dynamic Bond
Diversified portfolio of fixed income
instruments
(-3) to 8 years
Max 40% of total
assets below Baa
No Limitation(17)
PIMCO Strategic Bond
Diversified portfolio of fixed income
instruments
(-1) to 5 years
Max 20% of total
assets below Baa
No Limitation(18)
PIMCO Credit Opportunities Bond
Diversified portfolio of fixed income
instruments
0 to 6 years
Max 50% of total
assets below B-
No Limitation(5)
PIMCO TRENDS Managed Futures
Strategy
Financial and commodity-linked derivative
instruments selected by a quantitative strategy
and generally backed by a short to intermediate
duration portfolio which may consist of cash
equivalent securities and fixed income
instruments
N/A
No Limitation
No Limitation
PIMCO RAE Fundamental Advantage
PLUS
Long exposure to RAE US Large Model
Portfolio, short exposure to the S&P 500 Index,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(17)
PIMCO Climate Bond
Diversified portfolio of fixed income
instruments
2 to 8 years
Max 25% of total
assets below Baa
No Limitation(5)
Domestic
Equity-Related
PIMCO RAE PLUS
Exposure to RAE US Large Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(17)
PIMCO StocksPLUS® Small
Russell 2000® Index derivatives backed by a
diversified portfolio of actively managed fixed
income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS® Long Duration
S&P 500 Index derivatives backed by a
diversified portfolio of long-term fixed income
instruments
+/-2 years of
Bloomberg
Barclays
Long-Term
Government/Credit
Index(20)
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO StocksPLUS® Absolute Return
S&P 500 Index derivatives backed by a portfolio
of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(17)
PIMCO StocksPLUS®
S&P 500 Index derivatives backed by a portfolio
of short-term fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO RAE PLUS Small
Exposure to RAE US Small Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(13)
PIMCO RAE US
Exposure to RAE US Portfolio
N/A
N/A
0%
PIMCO RAE US Small
Exposure to RAE US Small Portfolio
N/A
N/A
0%

48  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
Equity-Related
PIMCO Dividend and Income
Exposure to RAE Income Global Portfolio in
Equity Sleeve; remainder of portfolio invests in
fixed income instruments of varying maturities
N/A
No Limitation
No Limitation
PIMCO RAE PLUS EMG
Exposure to RAE Emerging Markets Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO StocksPLUS® International
(Unhedged)
Non-U.S. equity derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS® International
(U.S. Dollar-Hedged)
Non-U.S. equity derivatives (hedged to
U.S. dollars) backed by a portfolio of fixed
income instruments.
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO RAE PLUS International
Exposure to RAE International Large Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE Worldwide Long/Short PLUS
Long exposure to RAE Low Volatility U.S. Model
Portfolio, RAE Low Volatility Intl Model Portfolio
and RAE Low Volatility EMG Model Portfolio,
short exposure to certain traditional
capitalization-weighted equity indexes,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE Emerging Markets
Exposure to RAE Emerging Markets Portfolio
N/A
N/A
No Limitation
PIMCO RAE International
Exposure to RAE International Portfolio
N/A
N/A
No Limitation
U.S. Government
Securities
PIMCO Government Money Market
U.S. government securities
≤ 60 days
dollar-weighted
average maturity
Min 97% of total
assets Prime 1; ≤ 3%
of total assets Prime 2
0%
Short Strategy
PIMCO StocksPLUS® Short
Short S&P 500 Index derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(17)
1
As rated by Moody's, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality.
2
Certain Underlying PIMCO Funds may invest beyond these limits in U.S. dollar-denominated instruments of non-U.S. issuers.
3
Such limitation shall not apply to the Fund's investments in mortgage- and asset-backed securities.
4
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 10% of its total assets.
5
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
6
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund. Information for the PIMCO Low Duration Credit Fund is effective as of May 3, 2021.
7
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 5% of its total assets.
8
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index.
9
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML Developed Markets High Yield Constrained (USD Hedged) Index.
10
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to within 10% (plus or minus) of the Fund's benchmark's foreign currency exposure.
11
The Fund may also invest up to an additional 5% of its total assets in mortgage-related high yield instruments rated below Baa.
12
Such limitation shall not apply to the Fund's investments in mortgage-related securities.
13
Within such limitation, the Fund may invest in mortgage-related securities rated below B.
14
The percentage limitation relates to Fixed Income Instruments of non-U.S. issuers denominated in any currency.
15
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or in Fixed Income Instruments denominated in the currencies of, emerging market countries, and in short-term investments.
16
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or Fixed Income Instruments denominated in the currencies of, emerging market countries and in Fixed Income Instruments, each of which may be represented by forwards or derivatives such as options, futures contracts or swap agreements.
17
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
18
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 25% of its total assets.
19
With respect to the Fund's fixed income investments, the Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
20
The Bloomberg Barclays Long-Term Government/Credit Index is an unmanaged index of U.S. Government or investment grade credit securities having a maturity of 10 years or more.

April 30, 2021 | PROSPECTUS  49

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Global Managed Asset Allocation Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$12.53
$0.12
$1.72
$1.84
$(0.98)
$(0.24)
$0.00
$(1.22)
12/31/2019
10.94
0.26
1.59
1.85
(0.26)
0.00
0.00
(0.26)
12/31/2018
12.83
0.29
(0.97)
(0.68)
(0.21)
(1.00)
0.00
(1.21)
12/31/2017
11.50
0.25
1.36
1.61
(0.28)
0.00
0.00
(0.28)
12/31/2016
11.33
0.24
0.21
0.45
0.00
0.00
(0.28)
(0.28)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratios shown do not include expenses of the investment companies in which the Portfolio may invest. See Note 9, Fees and Expenses, in the Notes to Financial Statements for more information regarding the expenses and any applicable fee waivers associated with these investments.

50  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets(d)
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$13.15
16.83%
$148,037
0.97%
1.17%
0.95%
1.15%
0.96%
360%
12.53
17.06
150,211
1.03
1.19
0.98
1.14
2.22
694
10.94
(5.46)
151,493
1.05
1.20
0.99
1.14
2.28
693
12.83
14.08
190,344
1.03
1.18
0.99
1.14
2.01
381
11.50
4.04
191,628
0.97
1.16
0.94
1.13
2.16
412

April 30, 2021 | PROSPECTUS  51

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1971F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
ACTIVE ASSET ALLOCATION PORTFOLIO – TOTAL RETURN ORIENTED
PIMCO Global Managed Asset Allocation Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Global Managed Asset Allocation Portfolio

Investment Objective
The Portfolio seeks total return which exceeds that of a blend of 60% MSCI World Index/40% Bloomberg Barclays U.S. Aggregate Index.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.95%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses
0.02%
Acquired Fund Fees and Expenses
0.22%
Total Annual Portfolio Operating Expenses(1)
1.44%
Fee Waiver and/or Expense Reimbursement(2)(3)
(0.20%)
Total Annual Portfolio Operating Expenses After Fee Waiver and/or
Expense Reimbursement(4)
1.24%
1
Total Annual Portfolio Operating Expenses do not match the Ratio of Expenses to Average Net Assets Excluding Waivers of the Portfolio, as set forth in the Financial Highlights table of the Portfolio’s prospectus, because the Ratio of Expenses to Average Net Assets Excluding Waivers reflects the operating expenses of the Portfolio and does not include Acquired Fund Fees and Expenses.
2
Pacific Investment Management Company LLC (“PIMCO”) has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the expenses attributable to the Management Fees of Underlying PIMCO Funds indirectly incurred by the Portfolio in connection with its investments in Underlying PIMCO Funds, to the extent the Portfolio’s Management Fees are greater than or equal to the Management Fees of the Underlying PIMCO Funds. This waiver renews annually for a full year unless terminated by PIMCO upon at least 30 days’ notice prior to the end of the contract term. For purposes of the expense reduction described above, references to Underlying PIMCO Funds include funds of PIMCO ETF Trust.
3
PIMCO has contractually agreed to waive the Portfolio’s advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Portfolio II Ltd. (the “GMAA Subsidiary”) to PIMCO. The GMAA Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO’s contract with the GMAA Subsidiary is in place.
4
“Other Expenses” and Acquired Fund Fees and Expenses include interest expense of the Portfolio and of the Underlying PIMCO Funds of 0.02% and 0.02%, respectively. Interest expense is borne by the Portfolio and the Underlying PIMCO Funds separately from the management fees paid to PIMCO. Excluding interest expense of the Portfolio and of the Underlying PIMCO Funds, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 1.20% for Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of
investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$126
$436
$768
$1,707
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 360% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio is intended for investors who prefer to have their asset allocation decisions made by professional investment managers. PIMCO uses a three-step approach in seeking to achieve the Portfolio’s investment objective which consists of 1) developing a target asset allocation; 2) developing a series of relative value strategies designed to add value beyond the target allocation; and 3) utilizing hedging techniques to manage risks. PIMCO evaluates these three steps and uses varying combinations of Acquired Funds and/or direct investments to implement them within the Portfolio. The Portfolio may invest in Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end investment companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management (“Underlying PIMCO Funds”), and may also invest in other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds (collectively, “Acquired Funds”).
The Portfolio seeks to achieve its investment objective by investing under normal circumstances in a combination of affiliated and unaffiliated funds, which may or may not be registered under the Investment Company Act of 1940, as amended (the “1940 Act”), Fixed Income Instruments, equity securities, forwards and derivatives. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio will invest in Acquired Funds, securities, instruments and other investments to the extent permitted under the 1940 Act, or any exemptive relief therefrom. To the extent the Portfolio invests in Underlying PIMCO Funds, PIMCO expects to select such Underlying PIMCO Funds without considering or canvassing the universe of available unaffiliated Acquired Funds. The Portfolio will

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

invest either directly or indirectly (through a fund) in instruments that are economically tied to at least three countries (one of which may be the United States).
The Portfolio seeks concurrent exposure to a broad spectrum of asset classes and other investments. The Portfolio will typically invest 50% to 70%, and under normal circumstances will invest a minimum of 20%, of its net assets in equity-related investments (including investment in common stock, preferred securities, equity securities of real estate investment trusts and/or investment in the Domestic Equity-Related Underlying PIMCO Funds, the International Equity-Related Underlying PIMCO Funds and the PIMCO RealEstateRealReturn Strategy Fund, an Underlying PIMCO Fund and in other equity-related Acquired Funds). The Portfolio may invest up to 5% of its net assets in real estate investment trusts. With respect to its direct or indirect (through a fund) investments in equity securities, there is no limitation on the market capitalization range of the issuers in which the Portfolio may invest. The Portfolio may invest up to 5% of its net assets in commodity-related investments (including exposure to commodity-related investments obtained through investment in the PIMCO Cayman Commodity Portfolio II Ltd., a wholly-owned subsidiary of the Portfolio organized under the laws of the Cayman Islands (the “GMAA Subsidiary”), and investment in the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, Underlying PIMCO Funds). The GMAA Subsidiary is advised by PIMCO and primarily invests in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments. As discussed in greater detail elsewhere in this prospectus, the GMAA Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. The Portfolio may invest up to 25% of its total assets in the GMAA Subsidiary. The Portfolio may invest up to 10% of its net assets in equity securities that are economically tied to emerging market countries. The Portfolio’s combined investments in equity securities tied to emerging market countries, commodity-related investments and real estate investment trusts will normally not exceed 15% of its net assets.
The Portfolio may invest up to 30% of its total assets in Fixed Income Instruments denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 15% of its total assets in Fixed Income Instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other Fixed Income Instruments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The average portfolio duration of this Portfolio normally varies from 0-6 years. Duration is a measure used to
determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio may purchase and sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales.
The Portfolio’s assets are not allocated according to a predetermined blend of shares of the Acquired Funds and/or direct investments in securities, instruments and other investments. Instead, when making allocation decisions among the Acquired Funds, securities, instruments and other investments, PIMCO considers various qualitative and quantitative factors relating to the U.S. and non-U.S. economies, and securities and commodities markets. These factors include projected growth trends in the U.S. and non-U.S. economies, forecasts for interest rates and the relationship between short- and long-term interest rates (yield curve), current and projected trends in inflation, relative valuation levels in the equity, fixed income, commodity and real estate markets and various segments within those markets, the outlook and projected growth of various industrial sectors, information relating to business cycles, borrowing needs and the cost of capital, political trends data relating to trade balances, and labor information. PIMCO uses these factors to help determine the Portfolio’s target asset allocation and to identify potentially attractive relative value and risk hedging strategies. PIMCO has the flexibility to reallocate the Portfolio’s assets among any or all of the investment exposures represented by affiliated or unaffiliated funds, or invest directly in securities, instruments and other investments, based on its ongoing analyses of the global economy and financial markets. While these analyses are performed daily, material shifts in investment exposures typically take place over longer periods of time.
As part of its investment process, PIMCO will seek to reduce exposure to certain risks by implementing various hedging transactions.
Once the target asset allocation, relative value strategies and risk hedging strategies have been determined, PIMCO then evaluates various combinations of affiliated or unaffiliated funds, securities, instruments and other investments to obtain the desired exposures and invests accordingly.
Additional information for these Underlying PIMCO Funds can be found in the Statement of Additional Information and the Underlying PIMCO Funds’ prospectuses and financial reports. Additional Underlying PIMCO Funds may be added or deleted in the future without shareholder notification.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio include risks from direct investments and/ or indirect exposure through investment in Acquired Funds. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are:
Allocation Risk:the risk that a Portfolio could lose money as a result of less than optimal or poor asset allocation decisions. The Portfolio could miss attractive investment opportunities by underweighting

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PIMCO Global Managed Asset Allocation Portfolio

markets that subsequently experience significant returns and could lose value by overweighting markets that subsequently experience significant declines
Acquired Fund Risk:the risk that a Portfolio's performance is closely related to the risks associated with the securities and other investments held by the Acquired Funds and that the ability of a Portfolio to achieve its investment objective will depend upon the ability of the Acquired Funds to achieve their investment objectives
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Distressed Company Risk:the risk that securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the
lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Commodity Risk:the risk that investing in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Real Estate Risk:the risk that the Portfolio’s investments in Real Estate Investment Trusts (“REITs”) or real estate-linked derivative instruments will subject the Portfolio to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. A Portfolio’s investments in REITs or real estate-linked derivative instruments subject it to management and tax risks. In addition, privately traded REITs subject a Portfolio to liquidity and valuation risk
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Smaller Company Risk:the risk that the value of securities issued by a smaller company may go up or down, sometimes rapidly and unpredictably as compared to more widely held securities, due to narrow markets and limited resources of smaller companies. A Portfolio’s investments in smaller companies subject it to greater levels of credit, market and issuer risk
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Tax Risk:the risk that the tax treatment of swap agreements and other derivative instruments, such as commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures, may be affected by future regulatory or legislative changes that could affect whether income from such investments is “qualifying income” under Subchapter M of the Internal Revenue Code, or otherwise affect the character, timing and/or amount of the Portfolio’s taxable income or gains and distributions
Subsidiary Risk:the risk that, by investing in the GMAA Subsidiary, the Portfolio is indirectly exposed to the risks associated with the GMAA Subsidiary’s investments. The GMAA Subsidiary is not registered under the 1940 Act and may not be subject to all the investor protections of the 1940 Act. There is no guarantee that the investment objective of the GMAA Subsidiary will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Value Investing Risk:a value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
Exchange-Traded Fund Risk:the risk that an exchange-traded fund may not track the performance of the index it is designed to track, among other reasons, because of exchange rules, market prices of shares of an exchange-traded fund may fluctuate rapidly and materially, or shares of an exchange-traded fund may trade significantly above or below net asset value, any of which may cause losses to the Portfolio invested in the exchange-traded fund
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

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PIMCO Global Managed Asset Allocation Portfolio

Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The 60% MSCI World Index/40% Bloomberg Barclays U.S. Aggregate Index is a blended index. The MSCI World Index is a free float-adjusted market capitalization weighted index that is designed to measure the equity market performance of developed markets. The MSCI World Index consists of 23 developed market country indices. The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable, and dollar denominated. The Bloomberg Barclays U.S. Aggregate Index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
June 30, 2020
15.67%
Worst Quarter
March 31, 2020
-13.94%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Advisor Class Return
16.71%
8.83%
4.59%
60% MSCI World Index/40% Bloomberg Barclays
U.S. Aggregate Index (reflects no deductions for fees,
expenses or taxes)
13.31%
9.34%
7.68%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Erin Browne, Geraldine Sundstrom and Emmanuel Sharef. Ms. Browne is a Managing Director of PIMCO and a senior portfolio manager in the Asset Allocation team and has managed the Portfolio since January 2019. Ms. Sundstrom is a Managing Director of PIMCO and a senior portfolio manager in the Asset Allocation team and has managed the Portfolio since July 2015. Dr. Sharef is an Executive Vice President of PIMCO and has managed the Portfolio since December 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

5  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
As the Portfolio may invest in shares of Acquired Funds, including the Underlying PIMCO Funds, the risks of investing in the Portfolio may be closely related to the risks associated with the Acquired Funds, including Underlying PIMCO Funds, and their investments. However, as the Portfolio may also invest its assets directly in stocks or bonds of other issuers and in other instruments, such as forwards, options, futures contracts or swap agreements, the Portfolio may be directly exposed to certain risks described below. As such, unless stated otherwise, any reference in this section to “Portfolios” includes both the Portfolio and Acquired Funds. Where necessary in this section, the Portfolio is specifically referred to as the “Portfolio.”
Allocation Risk
The Portfolio’s investment performance depends upon how its assets are allocated and reallocated according to the Portfolio’s asset allocation targets and ranges. A principal risk of investing in the Portfolio is that PIMCO will make less than optimal or poor asset allocation decisions. PIMCO attempts to identify investment allocations that will provide consistent, quality performance for the Portfolio, but there is no guarantee that such allocation techniques will produce the desired results. It is possible that PIMCO will focus on an investment that performs poorly or underperforms other investments under various market conditions. You could lose money on your investment in the Portfolio as a result of these allocation decisions.
Acquired Fund Risk
Because the Portfolio may invest its assets in Acquired Funds, the risks associated with investing in the Portfolio may be closely related to the risks associated with the securities and other investments held by the Acquired Funds. The ability of the Portfolio to achieve its investment objective may depend upon the ability of the Acquired Funds to achieve their respective investment objectives. There can be no assurance that the investment objective of any Acquired Fund will be achieved.
The Portfolio’s net asset value (“NAV”) will fluctuate in response to changes in the NAVs of the Acquired Funds in which it invests. The extent to which the investment performance and risks associated with the Portfolio correlates to those of a particular Acquired Fund will depend upon the extent to which the Portfolio’s assets are allocated from time to time for investment in the Acquired Fund, which may vary. As discussed under “Description of Principal Risks—Market Risk,” because the NAV of the Portfolio is related to the NAVs of the Acquired Funds in which it invests, inaccuracies, delays or other disruptions in the calculation of an Acquired Fund’s NAV may adversely impact the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the NAV of the Portfolio’s shares.

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the

April 30, 2021 | PROSPECTUS  7

PIMCO Variable Insurance Trust

Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Distressed Company Risk
The Portfolio’s investments in securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments. Issuers of distressed company securities may also be involved in restructurings or bankruptcy proceedings that may not be successful. An economic downturn or period of rising interest rates could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities (liquidity risk). If the issuer of a debt security is in default with respect to interest or principal payments, the Portfolio may lose its entire investment.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.

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Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio and certain Acquired Funds may rely on various third-party sources to calculate its NAV. As a result, the Portfolio and such Acquired Funds are subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s and Acquired Funds' calculations of their NAVs, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. Also, because the NAV of the Portfolio is related to the NAVs of the Acquired Funds in which it invests, the Portfolio may be adversely impacted by such inaccuracies, delays or other disruptions in the calculation of an Acquired Fund's NAV. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate,

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credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests. These factors include the possibility that the Portfolio's commodity derivatives positions may have different roll dates, reset dates or contract months than those specified in a particular commodity index.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio

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to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Commodity Risk
The Portfolio’s investments in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments. The GMAA Subsidiary and certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, may each concentrate its assets in a particular sector of the commodities market (such as oil, metal or agricultural products). As a result, the GMAA Subsidiary and certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, and, to the extent the Portfolio invests in the GMAA Subsidiary and/or certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, the Portfolio may be more susceptible to risks associated with those sectors. The prices for commodities in those sectors may fluctuate widely due to factors such as changes in value, supply and demand and governmental regulatory policies.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets

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in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Real Estate Risk
Investments in real estate investment trusts (“REITs”) or real estate-linked derivative instruments are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. An investment in a REIT or a real estate-linked derivative instrument that is linked to the value of a REIT is subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (the “Code”). In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. Finally, private REITs are not traded on a national securities exchange. As such, these products are generally illiquid. This reduces the ability of a Portfolio to redeem its investment early. Private REITs are also generally harder to value and may bear higher fees than public REITs.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leverage risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The GMAA Subsidiary will comply with these asset segregation or “earmarking” requirements to the same extent as the Portfolio. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy its obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities (or the value of the Acquired Funds). Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Smaller Company Risk
The general risks associated with fixed income securities and equity securities are particularly pronounced for securities issued by companies with smaller market capitalizations. These companies may have limited product lines, markets or financial resources or they may depend on a few key employees. As a result, they may be subject to greater levels of credit, market and issuer risk. Securities of smaller companies may trade less frequently and in lesser volumes than more widely held securities and their values may fluctuate more sharply than other securities. Companies with medium-sized market capitalizations may have risks similar to those of smaller companies.
Management Risk
The Portfolio, the GMAA Subsidiary and certain Acquired Funds are subject to management risk because they are actively managed investment portfolios. PIMCO or the sub-adviser, as applicable, or in the case of a fund that is not managed by PIMCO, such other fund’s investment adviser and sub-adviser, as applicable, and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, the GMAA Subsidiary and the Acquired Funds, as applicable, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio or an Acquired Fund seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio or Acquired Fund. To the extent the Portfolio or Acquired Fund employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio or Acquired Fund. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in

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value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Because a number of Underlying PIMCO Funds obtain exposure to certain proprietary model stock portfolios by investing in equity total return swaps based on such model portfolios, in other securities and instruments to replicate the performance of such model portfolios, or directly in the equity securities held in such model portfolios, such Underlying PIMCO Funds will be subject to the risks associated with the management of these proprietary model stock portfolios by the sub-adviser to such Underlying PIMCO Funds.
Tax Risk
The Portfolio and certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, gain exposure to the commodities markets through investments in commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures. The Portfolio may also gain exposure indirectly to commodity markets by investing in the GMAA Subsidiary, which invests primarily in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and/or other Fixed Income Instruments. In order for the Portfolio to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”), the Portfolio must derive at least 90 percent of its gross income each taxable year from certain qualifying sources of income.
As more fully described below under “Tax Consequences-A Note on the Portfolio,” the Internal Revenue Service (the “IRS”) issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. The IRS has issued private letter rulings in which the IRS specifically concluded that income derived from an investment in a subsidiary will also constitute qualifying income to the Portfolio. Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio‘s income from an investment in the subsidiary distributed annually or is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the Investment Company Act of 1940, as amended (the “1940 Act”).
The Portfolio will seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the GMAA Subsidiary. If the IRS were to determine that income derived from certain commodity-linked notes or from investments in the GMAA Subsidiary does not constitute qualifying income, the Portfolio and certain Underlying PIMCO Funds, including the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, might be adversely affected and would be required to reduce their exposure to such investments which might result in difficulty in implementing their investment strategies and increased costs and taxes.
The use of commodity index-linked notes and investments in the GMAA Subsidiary involve specific risks. See “Characteristics and Risks of Securities and Investment Techniques-Derivatives-A Note on the Portfolio” below for further information regarding commodity index-linked notes, including the risks associated with these instruments. In addition, see “Characteristics and Risks of Securities and Investment Techniques-Investments in the Wholly-Owned Subsidiary” below for further information regarding the GMAA Subsidiary, including the risks associated with investing in the GMAA Subsidiary.
Subsidiary Risk
By investing in the GMAA Subsidiary, the Portfolio is indirectly exposed to the risks associated with the GMAA Subsidiary’s investments. The investments held by the GMAA Subsidiary are generally similar to those that are permitted to be held by the Portfolio and are subject to the same risks that apply to similar investments if held directly by the Portfolio. These risks are described elsewhere in this prospectus. There can be no assurance that the investment objective of the Portfolio or the GMAA Subsidiary will be achieved.
The GMAA Subsidiary is not registered under the 1940 Act, and, unless otherwise noted in this prospectus, is not subject to all the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the GMAA Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the GMAA Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Value Investing Risk
Value investing attempts to identify companies that are believed to be undervalued. Value stocks typically have prices that are low relative to factors such as the company’s earnings, cash flow or dividends. A value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur. A value investing style may perform better or worse than equity portfolios that focus on growth stocks or that have a broader investment style.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.
Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
Exchange-Traded Fund (“ETF”) Risk
Investments in ETFs entail certain risks. Investments in ETFs designed to track an index involve the risk that the ETF’s performance may not track the performance of the index the ETF is designed to track. This deviation may occur due to cash inflows and outflows from and to investors buying and redeeming shares or due to occasional differences between the composition of the index and the securities held by the ETF. In addition, investments in ETFs involve the risk that the market prices of ETF shares will fluctuate, sometimes rapidly and materially, in response to changes in the ETF’s NAV, the value of ETF holdings and supply and demand for ETF shares. Although ETFs will generally trade close to NAV, market volatility, lack of an active trading market for ETF shares, disruptions at market participants (such as Authorized Participants or market makers) and any disruptions in the ordinary functioning of the creation/redemption process may result in ETF shares trading significantly above (at a “premium”) or below (at a “discount”) NAV. Significant losses may result when transacting in ETF shares in these and other circumstances.

April 30, 2021 | PROSPECTUS  15

PIMCO Variable Insurance Trust

LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters. PIMCO also serves as the investment adviser for the GMAA Subsidiary.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.95% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.90% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
As discussed in the “Portfolio Summary-Principal Investment Strategies” section, the Portfolio may pursue its investment objective by investing in the GMAA Subsidiary. The GMAA Subsidiary has entered into a separate contract with PIMCO whereby PIMCO provides investment advisory and other services to the GMAA Subsidiary. In consideration of these services, the GMAA Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. PIMCO has contractually agreed to waive the advisory fee and the supervisory and administrative fee it receives from the Portfolio in an amount equal to the management fee and administrative services fee, respectively, paid to PIMCO by the GMAA Subsidiary. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO’s contract with the GMAA Subsidiary is in place.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees at the annual rate of 0.05% for
Advisor Class shares (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not:

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Fund of Funds Fees
The Portfolio is permitted to invest in Underlying PIMCO Funds, which, for the Portfolio, is defined to include Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. The Portfolio is further permitted to invest in Acquired Funds, which, for the Portfolio, is defined to include the Underlying PIMCO Funds and other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds, which may or may not be registered under the 1940 Act.
The Portfolio pays advisory and supervisory and administrative fees directly to PIMCO at an annual rate stated above, based on the average daily net assets attributable in the aggregate to the Portfolio’s Advisor Class shares. The Portfolio also indirectly pays its proportionate share of the advisory, supervisory and administrative and management fees charged by PIMCO to the Underlying PIMCO Funds and, to the extent not included among the Underlying PIMCO Funds, funds of PIMCO ETF Trust in which the Portfolio invests (collectively, “Underlying PIMCO Fund Fees”).
PIMCO has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, to the extent necessary, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the Underlying PIMCO Fund Fees indirectly incurred by the Portfolio in connection with its investments in Underlying PIMCO Funds (for purposes of this expense reduction, this term includes funds of PIMCO ETF Trust), to the extent the Portfolio’s advisory fee or advisory fee and supervisory and administrative fee, taken together, are greater than or equal to the Underlying PIMCO Fund Fees. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term.
The Acquired Fund Fees and Expenses shown in the Annual Portfolio Operating Expenses table may be higher than the Underlying PIMCO Fund Fees used for purposes of the Expense Reduction shown in that table due to differences in the methods of calculation. The Acquired Fund Fees and Expenses, as required to be shown in the Annual Portfolio Operating Expenses table, are calculated using the total operating expenses for each Underlying PIMCO Fund (and any unaffiliated funds) over the Portfolio’s average net assets. The Underlying PIMCO Fund Fees that are used for purposes of implementing the expense reduction described above are calculated using the advisory and supervisory and administrative fees for each Underlying PIMCO Fund over the total assets invested in Underlying PIMCO Funds. Thus, the Acquired Fund Fees and Expenses listed in the Annual Portfolio Operating Expenses table will typically be higher than the Underlying PIMCO Fund Fees used to calculate the Expense Reduction when the Portfolio employs leverage as an investment strategy.
The expenses associated with investing in a fund of funds are generally higher than those for mutual funds that do not invest in other funds. The cost of investing in the Portfolio will generally be higher than the cost of investing in a Portfolio that invests directly in individual stocks and bonds. By investing in the Portfolio, an investor will indirectly bear fees and expenses charged by non-PIMCO Acquired Funds (and may indirectly bear a portion of the fees and expenses charged by Underlying PIMCO Funds to the extent such fees and expenses are not waived or reimbursed pursuant to applicable waiver and reimbursement agreements) in addition to the Portfolio’s direct fees and expenses. In addition, the use of a fund of funds structure could affect the timing, amount and character of distributions to shareholders and may therefore increase the amount of taxes payable by shareholders. The Portfolio, to the extent it invests in Underlying PIMCO Funds, invests in Institutional Class or Class M shares of the Underlying PIMCO Funds, which are not subject to any sales charges or distribution (12b-1) fees.
The following table summarizes the annual expenses borne by Institutional Class or Class M shareholders of the Underlying PIMCO Funds (or, in the case of those operating as exchange-traded funds, the Underlying PIMCO Fund shareholders). Because the Portfolio, to the extent it invests in Underlying PIMCO Funds, invests in Institutional Class or Class M shares of the Underlying PIMCO Funds, shareholders of the Portfolio would indirectly bear a proportionate share of these expenses, depending upon how the Portfolio’s assets are allocated from time to time among the Underlying PIMCO Funds.
For a complete description of an Underlying PIMCO Fund, please see the Underlying PIMCO Fund’s prospectus or offering memorandum, as applicable. For a summary description of the Underlying PIMCO Funds, please see the “Descriptions of the Underlying PIMCO Funds” section in this prospectus.
Annual Underlying PIMCO Fund Expenses
(Based on the average daily net assets attributable to an Underlying PIMCO Fund’s Institutional Class shares (or Class M shares in the case of the PIMCO Government Money Market Fund )).

April 30, 2021 | PROSPECTUS  19

PIMCO Variable Insurance Trust

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO California Intermediate Municipal Bond Fund
0.445%
0.00%
0.445%
PIMCO California Municipal Bond Fund
0.44%
0.02%
0.46%
PIMCO California Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Climate Bond Fund
0.50%
0.00%
0.50%
PIMCO CommoditiesPLUS® Strategy Fund
0.74%
0.27%
1.01%(3)
PIMCO CommodityRealReturn Strategy Fund®
0.74%
0.76%
1.50%(4)
PIMCO Credit Opportunities Bond Fund
0.90%
0.02%
0.92%
PIMCO Diversified Income Fund
0.75%
0.04%
0.79%
PIMCO Dividend and Income Fund
0.75%
0.05%
0.80%(5)
PIMCO Dynamic Bond Fund
0.80%
0.05%
0.85%
PIMCO Emerging Markets Bond Fund
0.83%
0.05%
0.88%
PIMCO Emerging Markets Corporate Bond Fund
0.90%
0.12%
1.02%
PIMCO Emerging Markets Currency and Short-Term Investments Fund
0.85%
0.03%
0.88%
PIMCO Emerging Markets Local Currency and Bond Fund
0.90%
0.80%
1.70%
PIMCO ESG Income Fund
0.50%
0.07%
0.57%(6)
PIMCO Extended Duration Fund
0.50%
1.21%
1.71%
PIMCO Global Advantage® Strategy Bond Fund
0.65%
0.21%
0.86%
PIMCO Global Bond Opportunities Fund (U.S. Dollar-Hedged)
0.55%
0.04%
0.59%
PIMCO Global Bond Opportunities Fund (Unhedged)
0.55%
0.12%
0.67%
PIMCO GNMA and Government Securities Fund
0.50%
0.33%
0.83%
PIMCO Government Money Market Fund
0.18%
0.00%
0.18%(7)
PIMCO High Yield Fund
0.55%
0.02%
0.57%
PIMCO High Yield Municipal Bond Fund
0.55%
0.08%
0.63%
PIMCO High Yield Spectrum Fund
0.60%
0.02%
0.62%
PIMCO Income Fund
0.50%
0.59%
1.09%
PIMCO International Bond Fund (U.S. Dollar-Hedged)
0.50%
0.10%
0.60%
PIMCO International Bond Fund (Unhedged)
0.50%
0.13%
0.63%
PIMCO Investment Grade Credit Bond Fund
0.50%
0.35%
0.85%
PIMCO Long Duration Total Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term Credit Bond Fund
0.55%
0.29%
0.84%
PIMCO Long-Term Real Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term U.S. Government Fund
0.475%
1.38%
1.855%
PIMCO Low Duration Credit Fund(8)
0.70%
0.05%
0.75%
PIMCO Low Duration ESG Fund
0.50%
0.08%
0.58%
PIMCO Low Duration Fund
0.46%
0.41%
0.87%
PIMCO Low Duration Fund II
0.50%
0.03%
0.53%
PIMCO Low Duration Income Fund
0.50%
0.05%
0.55%
PIMCO Moderate Duration Fund
0.46%
0.15%
0.61%
PIMCO Mortgage Opportunities and Bond Fund
0.60%
1.22%
1.82%
PIMCO Mortgage-Backed Securities Fund
0.50%
0.25%
0.75%
PIMCO Municipal Bond Fund
0.44%
0.07%
0.51%
PIMCO National Intermediate Municipal Bond Fund
0.45%
0.00%
0.45%
PIMCO New York Municipal Bond Fund
0.445%
0.05%
0.495%
PIMCO Preferred and Capital Securities Fund
0.79%
0.09%
0.88%(9)
PIMCO RAE Emerging Markets Fund
0.75%
0.02%
0.77%(10)
PIMCO RAE Fundamental Advantage PLUS Fund
0.89%
0.07%
0.96%
PIMCO RAE International Fund
0.50%
0.02%
0.52%(5)
PIMCO RAE PLUS EMG Fund
1.10%
0.21%
1.31%
PIMCO RAE PLUS Fund
0.79%
0.08%
0.87%
PIMCO RAE PLUS International Fund
0.82%
0.05%
0.87%
PIMCO RAE PLUS Small Fund
0.84%
0.09%
0.93%
PIMCO RAE US Fund
0.40%
0.02%
0.42%(5)

20  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO RAE US Small Fund
0.50%
0.04%
0.54%
PIMCO RAE Worldwide Long/Short PLUS Fund
1.19%
0.09%
1.28%
PIMCO Real Return Fund
0.45%
0.08%
0.53%
PIMCO RealEstateRealReturn Strategy Fund
0.74%
1.36%
2.10%
PIMCO Short Asset Investment Fund
0.34%
0.02%
0.36%
PIMCO Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Short-Term Fund
0.45%
0.10%
0.55%
PIMCO StocksPLUS® Absolute Return Fund
0.64%
0.08%
0.72%
PIMCO StocksPLUS® Fund
0.50%
0.06%
0.56%
PIMCO StocksPLUS® International Fund (U.S. Dollar-Hedged)
0.75%
0.25%
1.00%
PIMCO StocksPLUS® International Fund (Unhedged)
0.64%
0.38%
1.02%
PIMCO StocksPLUS® Long Duration Fund
0.59%
0.42%
1.01%
PIMCO StocksPLUS® Short Fund
0.64%
0.45%
1.09%
PIMCO StocksPLUS® Small Fund
0.69%
0.06%
0.75%
PIMCO Strategic Bond Fund
0.55%
0.02%
0.57%(11)
PIMCO Total Return ESG Fund
0.50%
0.46%
0.96%
PIMCO Total Return Fund
0.46%
0.24%
0.70%
PIMCO Total Return Fund II
0.50%
0.26%
0.76%
PIMCO Total Return Fund IV
0.50%
0.30%
0.80%
PIMCO TRENDS Managed Futures Strategy Fund
1.40%
0.29%
1.69%(12)
1
“Management Fees” reflects an advisory fee and a supervisory and administrative fee payable by an Underlying PIMCO Fund to PIMCO.
2
Other Expenses include expenses such as organizational expenses, interest expense, taxes, governmental fees, pro rata Trustees' fees and acquired fund fees and expenses attributable to the Institutional Class or Class M shares or the Fund in the case of exchange-traded funds of the PIMCO ETF Trust or PIMCO Equity Series.
3
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund III Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
4
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund I Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
5
PIMCO has contractually agreed, through October 31, 2021, to waive a portion of the Fund's supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund's organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Equity Series at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
6
PIMCO has contractually agreed, through July 31, 2022, to waive a portion of the Fund’s supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
7
To maintain certain net yields for the Fund, PIMCO or its affiliates may temporarily and voluntarily waive, reduce or reimburse all or any portion of the Fund's fees and expenses.
8
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund.
9
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Capital Securities Fund (Cayman) Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
10
PIMCO has contractually agreed, through July 31, 2022, to reduce its supervisory and administrative fee for each share class of the Fund by 0.05% of the average daily net assets attributable to the applicable class of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years from the date of waiver.
11
PIMCO has contractually agreed, through July 31, 2022, to reduce its advisory fee by 0.10% of the average daily net assets of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years.

April 30, 2021 | PROSPECTUS  21

PIMCO Variable Insurance Trust

12
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund VIII, Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
Individual Portfolio Managers
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Global Managed Asset Allocation
Erin Browne
1/19
Managing Director, PIMCO. Ms. Browne is a portfolio manager in the Newport Beach office,
focusing on multi-asset strategies. In her role, she works with PIMCO's asset allocation team
and with portfolio managers across asset classes and sectors globally. Prior to joining
PIMCO in 2018, Ms. Browne was a managing director and head of asset allocation at UBS
Asset Management, helping to drive the firm's macro research, capital market assumptions,
tactical asset allocation and strategic asset allocation views across asset classes. Previously,
she was head of macro investments at UBS O'Connor, a multi-strategy hedge fund manager,
and a global macro portfolio manager at Point72 Asset Management. Ms. Browne has also
held roles at Citigroup, Moore Capital Management and Neuberger Berman, and she began
her career at Lehman Brothers. She has investment experience since 2002 and holds a
bachelor's degree in economics from Georgetown University.
PIMCO Global Managed Asset Allocation
Emmanuel Sharef
12/19
Executive Vice President, PIMCO. Dr. Sharef is an executive vice president and portfolio
manager in the Newport Beach office, focused on asset allocation strategies and the
residential real estate market. He is a member of the Americas Portfolio Committee and has
served as a rotating member of the Investment Committee. Prior to joining PIMCO in 2011,
he worked in the mortgage credit strategists group at Morgan Stanley. He has investment
and financial services experience since 2008 and holds a Ph.D. in operations research from
Cornell University, specializing in statistics and biometrics. He received an undergraduate
degree from Princeton University.
PIMCO Global Managed Asset Allocation
Geraldine Sundstrom
7/15
Managing Director, PIMCO. Ms. Sundstrom is a portfolio manager in the London office,
focusing on asset allocation strategies. Prior to joining PIMCO in 2015, she was a partner
and portfolio manager at Brevan Howard, where she led the Emerging Markets Strategies
Fund. Previously, she was a portfolio manager at Moore Capital Management. She has
investment experience since 1996 and holds a master's degree in finance from Birkbeck
College at London University and two degrees from Universite Paris Dauphine.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

22  Prospectus | PIMCO Variable Insurance Trust

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PIMCO Variable Insurance Trust

Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

24  Prospectus | PIMCO Variable Insurance Trust

Prospectus

From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

April 30, 2021 | PROSPECTUS  25

PIMCO Variable Insurance Trust

thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

26  Prospectus | PIMCO Variable Insurance Trust

Prospectus

circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

April 30, 2021 | PROSPECTUS  27

PIMCO Variable Insurance Trust

the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
A Note on the Portfolio. One of the requirements for favorable tax treatment as a regulated investment company under the Code is that the Portfolio derives at least 90% of its gross income from certain qualifying sources of income. The IRS has issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. As such, the Portfolio’s ability to utilize commodity-linked swaps as part of its investment strategy is limited to a maximum of 10% of its gross income.
However, in a subsequent revenue ruling, the IRS provides that income from alternative investment instruments (such as certain commodity index-linked notes) that create commodity exposure may be considered qualifying income under the Code. The IRS has also issued private letter

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rulings in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued private letter rulings in which the IRS specifically concluded that income derived from an investment in a subsidiary will also constitute qualifying income, even if that subsidiary itself owns commodity-linked swaps. The Portfolio will continue to seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the GMAA Subsidiary.
Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio‘s income from an investment in the subsidiary is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the 1940 Act. In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings. There can be no assurance that the IRS will not change its position with respect to some or all of these conclusions or that future legislation will not adversely impact the tax treatment of the Portfolio’s commodity-linked investments. If the IRS were to change or reverse its position, or if future legislation adversely affected the tax treatment of the Portfolio’s commodity-linked investments, there would likely be a significant adverse impact on the Portfolio, including the possibility of failing to qualify as a regulated investment company. If the Portfolio did not qualify as a regulated investment company for any taxable year, its taxable income would be subject to tax at the Portfolio level at regular corporate tax rates (without reduction for distributions to shareholders) and to a further tax at the shareholder level when such income is distributed. Furthermore, the tax treatment of commodity-linked notes, other commodity-linked derivatives, and the Portfolio’s investments in the GMAA Subsidiary may otherwise be adversely affected by future legislation, court decisions, Treasury Regulations and/or guidance issued by the IRS. Such developments could affect the character, timing and/or amount of the Portfolio’s taxable income or any distribution made by the Portfolio or result in the inability of the Portfolio to operate as described in this Prospectus.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
As the Portfolio may invest in shares of the Acquired Funds, the risks of investing in the Portfolio may be closely related to the risks associated with the Acquired Funds and their investments. However, as the Portfolio may also invest its assets directly in Fixed Income Instruments, equity securities, forwards or derivatives, such as options, futures
contracts or swap agreements, other affiliated or unaffiliated funds, and other investments, the Portfolio may be directly exposed to certain risks described below.
This section provides additional information about some of the principal investments and related risks of the Portfolio and of certain Acquired Funds described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio and certain Acquired Funds from time to time. Generally, the characteristics and risks of securities and investment techniques that may be used by the Acquired Funds from time to time are similar to those described below. However, the risks associated with an Acquired Fund’s investments are described more fully in each Acquired Fund’s prospectus. Accordingly, please see an Acquired Fund’s prospectus for a more complete description of the Acquired Fund and the risks associated with its investments.
Most of these securities and investment techniques described herein are discretionary, which means that PIMCO, or in the case of a fund that is not managed by PIMCO, such fund’s investment adviser and sub-adviser, as applicable, can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio or Acquired Funds. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Because the Portfolio may invest a portion of its assets in the GMAA Subsidiary, which may hold some of the investments described in this prospectus, the Portfolio may be indirectly exposed to the risks associated with those investments. With respect to its investments, the GMAA Subsidiary will generally be subject to the same fundamental, non- fundamental and certain other investment restrictions as the Portfolio; however, the GMAA Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity- linked derivative instruments. The Portfolio and the GMAA Subsidiary may test for compliance with certain investment restrictions on a consolidated basis, except that with respect to their investments in certain securities that may involve leverage, the GMAA Subsidiary will comply with asset segregation or “earmarking” requirements to the same extent as the Portfolio.
Investors should be aware that the investments made by a Portfolio and the results achieved by a Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to a Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact a Portfolio’s portfolio management.

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For example, a Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause Portfolios to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase a Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause a Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect a Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.

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Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal
Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is

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funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity
absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.

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One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore,

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the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds,

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the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and
equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this Prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions. Preferred and other senior

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securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights. Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time. In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
While certain Underlying PIMCO Funds will generally invest in equity derivatives, each such Underlying PIMCO Fund may invest without limit directly in equity securities, including common stocks, preferred securities and convertible securities. In addition, the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, each an Underlying PIMCO Fund, may invest in equity securities of issuers in commodity-related industries, and the PIMCO RealEstateRealReturn Strategy Fund, an Underlying PIMCO Fund, may invest in REITs and equity securities of issuers in real estate-related industries. The Portfolio may also invest directly in equity securities. When investing directly in equity securities, the Portfolio will not be limited to only those equity securities with any particular weighting in the Portfolio’s benchmark index, if any. Generally, the Portfolio may consider investing directly in equity securities when derivatives on the underlying securities appear to be overvalued.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.
The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined

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by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,
PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for

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many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign
currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.

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Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with

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many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or
holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
A Note on the Portfolio. In light of relevant IRS guidance, as discussed above under “Tax Consequences—A Note on the Portfolio,” the Portfolio will seek to gain exposure to the commodity markets primarily through investments in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices, and through investments in the GMAA Subsidiary (as discussed below). The Portfolio may also invest in commodity-linked notes with principal and/or coupon payments linked to the value of particular commodities or commodity futures contracts, or a subset of commodities and commodities futures contracts. These notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the

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note. The value of these notes will rise or fall in response to changes in the underlying commodity, commodity futures contract, subset of commodities, subset of commodities futures contracts or commodity index.
These notes expose the Portfolio economically to movements in commodity prices. These notes also are subject to risks, such as credit, market and interest rate risks, that in general affect the values of debt securities. In addition, these notes are often leveraged, increasing the volatility of each note’s market value relative to changes in the underlying commodity, commodity futures contract or commodity index. Therefore, at the maturity of the note, the Portfolio may receive more or less principal than it originally invested. The Portfolio might receive interest payments on the note that are more or less than the stated coupon interest payments.
The Portfolio may also invest in other commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures. The value of a commodity-linked derivative investment generally is based upon the price movements of a physical commodity (such as energy, mineral, or agricultural products), a commodity futures contract, a subset of commodities, a subset of commodities futures contracts or commodity index, or other economic variable based upon changes in the value of commodities or the commodities markets.
Options transactions may be effected on exchanges or in the OTC market. When OTC options are purchased, the Portfolio’s portfolio bears the risk that the counterparty that wrote the option will be unable or unwilling to perform its obligations under the option contract. Options may also be illiquid and, in such cases, the Portfolio may have difficulty closing out its position. OTC options also may include options on baskets of specific securities.
Many swap transactions are privately negotiated agreements between the Portfolio and a counterparty to exchange or swap investment cash flows or assets at specified intervals in the future. The obligations may extend beyond one year. There is often no central exchange for swap transactions and therefore they can be less liquid investments than exchange-traded instruments. The Dodd-Frank Act and related regulatory developments require the clearing and exchange-trading of certain standardized OTC derivative instruments that the CFTC and SEC have defined as “swaps.” The CFTC has implemented mandatory exchange- trading and clearing requirements under the Dodd-Frank Act and the CFTC continues to approve contracts for central clearing. Uncleared swaps are subject to margin requirements that are being implemented on a phased-in basis. The investment adviser will continue to monitor these developments, particularly to the extent regulatory changes affect a Portfolio’s ability to enter into swap agreements.
As described below under “Characteristics and Risks of Securities and Investment Techniques—Investments in the Wholly-Owned Subsidiary,” the Portfolio may gain exposure to commodity markets by investing in the GMAA Subsidiary. It is expected that the GMAA Subsidiary will invest primarily in commodity-linked derivative instruments, including
swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments.
The IRS issued a revenue ruling that limits the extent to which the Portfolio may invest directly in commodity-linked swaps or certain other commodity- linked derivatives. The GMAA Subsidiary, on the other hand, may invest in these commodity-linked derivatives generally without limitation. See “Tax Consequences—A Note on the Portfolio,” above for further information.
Investments in a Wholly Owned Subsidiary
Investments in the GMAA Subsidiary are expected to provide the Portfolio with exposure to the commodity markets within the limitations of Subchapter M of the Code and recent IRS revenue rulings, as discussed above under “Tax Consequences—A Note on the Portfolio.”
It is expected that the GMAA Subsidiary will invest primarily in commodity- linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation- indexed securities and other Fixed Income Instruments. Although the Portfolio may enter into these commodity-linked derivative instruments directly, the Portfolio will likely gain exposure to these derivative instruments indirectly by investing in the GMAA Subsidiary. To the extent that PIMCO believes that these commodity-linked derivative instruments are better suited to provide exposure to the commodities market than commodity index-linked notes, the Portfolio’s investment in the GMAA Subsidiary will likely increase. The GMAA Subsidiary will also invest in inflation-indexed securities and/or other Fixed Income Instruments, which are intended to serve as margin or collateral for the GMAA Subsidiary’s derivatives position, common and preferred securities as well as convertible securities of issuers in commodity-related industries, collateralized debt obligations, event-linked bonds and event-linked swaps. To the extent that the Portfolio invests in the GMAA Subsidiary, it may be subject to the risks associated with those derivative instruments and other securities, which are discussed elsewhere in this prospectus.
While the GMAA Subsidiary may be considered similar to an investment company, it is not registered under the 1940 Act and, unless otherwise noted in the prospectus, is not subject to all of the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the GMAA Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the GMAA Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders

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PIMCO Variable Insurance Trust

substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in Underlying PIMCO Funds and, to the extent permitted by the 1940 Act or exemptive relief therefrom, other affiliated and unaffiliated funds, which may or may not be registered under the 1940 Act, such as open-end or closed-end management investment companies, exchange-traded funds and exchange-traded vehicles. Other unaffiliated investment companies are not required to make their shares available for purchase by the Portfolio, and there is no guarantee that such investment will be, or will continue to be, available. Each Underlying PIMCO Fund may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or

42  Prospectus | PIMCO Variable Insurance Trust

Prospectus

other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The limitation described in the foregoing sentence shall not apply to the Portfolio’s investment in the GMAA Subsidiary. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio and each Underlying PIMCO Fund may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act, and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire,
convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities

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PIMCO Variable Insurance Trust

lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. In addition to indirectly bearing the expenses associated with portfolio turnover of the Acquired Funds, the Portfolio will directly bear these expenses to the extent that it invests in other securities and instruments.  Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objectives of the Portfolio and certain Underlying PIMCO Funds are non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval. The investment objectives of certain Underlying PIMCO Funds are fundamental and may not be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.

44  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, sub-advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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PIMCO Variable Insurance Trust

Descriptions of the Underlying PIMCO Funds
The Portfolio may invest its assets in some or all of the Underlying PIMCO Funds, which for the Portfolio, is defined to include Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end investment companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. The Portfolio is further permitted to invest in Acquired Funds, which, for the Portfolio, is defined to include the Underlying PIMCO Funds and other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds, which may or may not be registered under the 1940 Act. Because the Underlying PIMCO Funds are not offered in this prospectus, the following provides a general description of the main investments and other information about the Underlying PIMCO Funds. At the discretion of PIMCO and without shareholder approval, the Portfolio may invest in additional Underlying PIMCO Funds created in the future. For a complete description of an Underlying PIMCO Fund, please see that Fund’s Institutional Class or Class M prospectus, which is incorporated herein by reference and is available free of charge by telephoning 1-800-927-4648.
Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Short Duration
PIMCO Low Duration Income
Short maturity fixed income instruments
0 to 3 years
Max 30% of total
assets below Baa(3)
No Limitation(4)
PIMCO Short Asset Investment
Money market instruments and short maturity
fixed income instruments
≤ 1.5 years
Baa to Aaa
0%
PIMCO Short-Term
Money market instruments and short maturity
fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below Baa
0-10% of total
assets(5)
PIMCO Low Duration
Short maturity fixed income instruments
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration II
Short maturity fixed income instruments with
quality and non-U.S. issuer restrictions
1 to 3 years
A to Aaa
0%
PIMCO Low Duration ESG
Short maturity fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration Credit(6)
Diversified portfolio of fixed income
instruments
0 to 3 years
Max 10% of total
assets below Caa
0-25% of total
assets(7)
Intermediate
Duration
PIMCO Moderate Duration
Short and intermediate maturity fixed income
instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO GNMA and Government
Securities
Short and intermediate maturity
mortgage-related fixed income securities issued
by the Government National Mortgage
Association and U.S. government securities
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa
0%
PIMCO High Yield
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(8) max
20% of total assets
Caa or below
0-20% of total
assets(5)
PIMCO High Yield Spectrum
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(9)
No Limitation(10)
PIMCO Mortgage-Backed Securities
Short and intermediate maturity
mortgage-related fixed income instruments
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa(11)
0%
PIMCO Total Return
Intermediate maturity fixed income instruments
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return II
Intermediate maturity fixed income instruments
with quality and non-U.S. issuer restrictions
+/-2 years of its
benchmark
Baa to Aaa
0%
PIMCO Total Return ESG
Intermediate maturity fixed income instruments
with prohibitions on firms engaged in socially
sensitive practices
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return IV
Intermediate maturity fixed income instruments
+/-1.5 years of its
benchmark
Baa to Aaa
0-15% of total
assets(7)
PIMCO Investment Grade Credit Bond
Investment grade fixed income securities
+/-2 years of its
benchmark
Max 15% of total
assets below Baa
0-30% of total
assets(5)

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Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Long Duration
PIMCO Long Duration Total Return
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Extended Duration
Long-term maturity fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO Long-Term U.S. Government
Long-term maturity fixed income securities
≥ 8 years
A to Aaa; max 25% Aa;
max 10% A
0%
PIMCO Mortgage Opportunities and
Bond
Mortgage-related assets and fixed income
instruments
(-1) to 8 years
Max 50% of total
assets below Baa(12)
0%
PIMCO Long-Term Credit Bond
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
B to Aaa; max 20% of
total assets below Baa
0-30% of total
assets(5)
Income
PIMCO ESG Income
Broad range of fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Income
Broad range of fixed income instruments
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Preferred and Capital Securities
Capital securities and preferred securities
+/-2 years of its
benchmark
No Limitation
No Limitation(4)
Inflation-Related
PIMCO Real Return
Inflation-indexed fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO Long-Term Real Return
Inflation-indexed fixed income securities
+/-4 years of its
benchmark
B to Aaa; max 20% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO CommoditiesPLUS® Strategy
Commodity-linked derivative instruments
backed by an actively managed low volatility
portfolio of fixed income instruments
≤ 1 year
Max 10% of total
assets below Baa
0-20%(4)
PIMCO CommodityRealReturn Strategy®
Commodity-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO RealEstateRealReturn Strategy
Real estate-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
Tax Exempt
PIMCO California Short Duration
Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal and California
income tax)
≤ 3 years
Caa to Aaa; max 10%
of total assets below
Baa
0%
PIMCO California Municipal Bond
Municipal securities (exempt from federal and
California income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO Short Duration Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal income tax)
≤ 3 years
Baa to Aaa
0%
PIMCO California Intermediate Municipal
Bond
Intermediate maturity municipal securities
(exempt from federal and California income
tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO National Intermediate Municipal
Bond
Municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO New York Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal and New York
income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO High Yield Municipal Bond
Intermediate to long-term maturity high yield
municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
No Limitation
0%

April 30, 2021 | PROSPECTUS  47

PIMCO Variable Insurance Trust

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
PIMCO Emerging Markets Bond
Emerging market fixed income instruments
+/- 2 years of its
benchmark
Max 15% of total
assets below B
≥ 80% of assets(14)
PIMCO Emerging Markets Currency and
Short-Term Investments
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and short-term investments
≤ 2 years
Max 15% of total
assets below B
No Limitation(15)
PIMCO International Bond
(U.S. Dollar-Hedged)
Intermediate maturity hedged non-U.S. fixed
income instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO International Bond (Unhedged)
Intermediate maturity non-U.S. fixed income
instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation
PIMCO Global Advantage® Strategy
Bond
U.S. and non-U.S. fixed income instruments
≤ 8 years
Max 15% of total
assets below B
No Limitation
PIMCO Global Bond Opportunities
(U.S. Dollar-Hedged)
U.S. and hedged non-U.S. intermediate maturity
fixed income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO Global Bond Opportunities
(Unhedged)
U.S. and non-U.S. intermediate maturity fixed
income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation
PIMCO Diversified Income
Investment grade corporate, high yield and
emerging market fixed income instruments
3 to 8 years
Max 10% below B
No Limitation
PIMCO Emerging Markets Local Currency
and Bond
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and fixed income instruments
+/-2 years of its
benchmark
Max 15% of total
assets below B
No Limitation(16)
PIMCO Emerging Markets Corporate
Bond
Diversified portfolio of fixed income
instruments economically tied to emerging
market countries
+/- 2 years of its
benchmark
Max 15% of total
assets below B
No Limitation
Absolute Return
PIMCO Dynamic Bond
Diversified portfolio of fixed income
instruments
(-3) to 8 years
Max 40% of total
assets below Baa
No Limitation(17)
PIMCO Strategic Bond
Diversified portfolio of fixed income
instruments
(-1) to 5 years
Max 20% of total
assets below Baa
No Limitation(18)
PIMCO Credit Opportunities Bond
Diversified portfolio of fixed income
instruments
0 to 6 years
Max 50% of total
assets below B-
No Limitation(5)
PIMCO TRENDS Managed Futures
Strategy
Financial and commodity-linked derivative
instruments selected by a quantitative strategy
and generally backed by a short to intermediate
duration portfolio which may consist of cash
equivalent securities and fixed income
instruments
N/A
No Limitation
No Limitation
PIMCO RAE Fundamental Advantage
PLUS
Long exposure to RAE US Large Model
Portfolio, short exposure to the S&P 500 Index,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(17)
PIMCO Climate Bond
Diversified portfolio of fixed income
instruments
2 to 8 years
Max 25% of total
assets below Baa
No Limitation(5)
Domestic
Equity-Related
PIMCO RAE PLUS
Exposure to RAE US Large Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(17)
PIMCO StocksPLUS® Small
Russell 2000® Index derivatives backed by a
diversified portfolio of actively managed fixed
income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS® Long Duration
S&P 500 Index derivatives backed by a
diversified portfolio of long-term fixed income
instruments
+/-2 years of
Bloomberg
Barclays
Long-Term
Government/Credit
Index(20)
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO StocksPLUS® Absolute Return
S&P 500 Index derivatives backed by a portfolio
of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(17)
PIMCO StocksPLUS®
S&P 500 Index derivatives backed by a portfolio
of short-term fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO RAE PLUS Small
Exposure to RAE US Small Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(13)
PIMCO RAE US
Exposure to RAE US Portfolio
N/A
N/A
0%
PIMCO RAE US Small
Exposure to RAE US Small Portfolio
N/A
N/A
0%

48  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
Equity-Related
PIMCO Dividend and Income
Exposure to RAE Income Global Portfolio in
Equity Sleeve; remainder of portfolio invests in
fixed income instruments of varying maturities
N/A
No Limitation
No Limitation
PIMCO RAE PLUS EMG
Exposure to RAE Emerging Markets Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO StocksPLUS® International
(Unhedged)
Non-U.S. equity derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS® International
(U.S. Dollar-Hedged)
Non-U.S. equity derivatives (hedged to
U.S. dollars) backed by a portfolio of fixed
income instruments.
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO RAE PLUS International
Exposure to RAE International Large Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE Worldwide Long/Short PLUS
Long exposure to RAE Low Volatility U.S. Model
Portfolio, RAE Low Volatility Intl Model Portfolio
and RAE Low Volatility EMG Model Portfolio,
short exposure to certain traditional
capitalization-weighted equity indexes,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE Emerging Markets
Exposure to RAE Emerging Markets Portfolio
N/A
N/A
No Limitation
PIMCO RAE International
Exposure to RAE International Portfolio
N/A
N/A
No Limitation
U.S. Government
Securities
PIMCO Government Money Market
U.S. government securities
≤ 60 days
dollar-weighted
average maturity
Min 97% of total
assets Prime 1; ≤ 3%
of total assets Prime 2
0%
Short Strategy
PIMCO StocksPLUS® Short
Short S&P 500 Index derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(17)
1
As rated by Moody's, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality.
2
Certain Underlying PIMCO Funds may invest beyond these limits in U.S. dollar-denominated instruments of non-U.S. issuers.
3
Such limitation shall not apply to the Fund's investments in mortgage- and asset-backed securities.
4
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 10% of its total assets.
5
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
6
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund. Information for the PIMCO Low Duration Credit Fund is effective as of May 3, 2021.
7
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 5% of its total assets.
8
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index.
9
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML Developed Markets High Yield Constrained (USD Hedged) Index.
10
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to within 10% (plus or minus) of the Fund's benchmark's foreign currency exposure.
11
The Fund may also invest up to an additional 5% of its total assets in mortgage-related high yield instruments rated below Baa.
12
Such limitation shall not apply to the Fund's investments in mortgage-related securities.
13
Within such limitation, the Fund may invest in mortgage-related securities rated below B.
14
The percentage limitation relates to Fixed Income Instruments of non-U.S. issuers denominated in any currency.
15
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or in Fixed Income Instruments denominated in the currencies of, emerging market countries, and in short-term investments.
16
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or Fixed Income Instruments denominated in the currencies of, emerging market countries and in Fixed Income Instruments, each of which may be represented by forwards or derivatives such as options, futures contracts or swap agreements.
17
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
18
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 25% of its total assets.
19
With respect to the Fund's fixed income investments, the Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
20
The Bloomberg Barclays Long-Term Government/Credit Index is an unmanaged index of U.S. Government or investment grade credit securities having a maturity of 10 years or more.

April 30, 2021 | PROSPECTUS  49

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Global Managed Asset Allocation Portfolio
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$12.60
$0.10
$1.72
$1.82
$(0.96)
$(0.24)
$0.00
$(1.20)
12/31/2019
10.99
0.25
1.61
1.86
(0.25)
0.00
0.00
(0.25)
12/31/2018
12.89
0.28
(0.98)
(0.70)
(0.20)
(1.00)
0.00
(1.20)
12/31/2017
11.55
0.23
1.37
1.60
(0.26)
0.00
0.00
(0.26)
12/31/2016
11.38
0.23
0.21
0.44
0.00
0.00
(0.27)
(0.27)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratios shown do not include expenses of the investment companies in which the Portfolio may invest. See Note 9, Fees and Expenses, in the Notes to Financial Statements for more information regarding the expenses and any applicable fee waivers associated with these investments.

50  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets(d)
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$13.22
16.62%
$447,404
1.07%
1.27%
1.05%
1.25%
0.86%
360%
12.60
17.05
440,736
1.13
1.29
1.08
1.24
2.12
694
10.99
(5.61)
436,873
1.15
1.30
1.09
1.24
2.18
693
12.89
13.99
549,934
1.13
1.28
1.09
1.24
1.90
381
11.55
3.92
569,112
1.07
1.26
1.04
1.23
2.07
412

April 30, 2021 | PROSPECTUS  51

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1972S_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
ACTIVE ASSET ALLOCATION PORTFOLIO – TOTAL RETURN ORIENTED
PIMCO Global Managed Asset Allocation Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Global Managed Asset Allocation Portfolio

Investment Objective
The Portfolio seeks total return which exceeds that of a blend of 60% MSCI World Index/40% Bloomberg Barclays U.S. Aggregate Index.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.95%
Other Expenses
0.02%
Acquired Fund Fees and Expenses
0.22%
Total Annual Portfolio Operating Expenses(1)
1.19%
Fee Waiver and/or Expense Reimbursement(2)(3)
(0.20%)
Total Annual Portfolio Operating Expenses After Fee Waiver and/or
Expense Reimbursement(4)
0.99%
1
Total Annual Portfolio Operating Expenses do not match the Ratio of Expenses to Average Net Assets Excluding Waivers of the Portfolio, as set forth in the Financial Highlights table of the Portfolio’s prospectus, because the Ratio of Expenses to Average Net Assets Excluding Waivers reflects the operating expenses of the Portfolio and does not include Acquired Fund Fees and Expenses.
2
Pacific Investment Management Company LLC (“PIMCO”) has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the expenses attributable to the Management Fees of Underlying PIMCO Funds indirectly incurred by the Portfolio in connection with its investments in Underlying PIMCO Funds, to the extent the Portfolio’s Management Fees are greater than or equal to the Management Fees of the Underlying PIMCO Funds. This waiver renews annually for a full year unless terminated by PIMCO upon at least 30 days’ notice prior to the end of the contract term. For purposes of the expense reduction described above, references to Underlying PIMCO Funds include funds of PIMCO ETF Trust.
3
PIMCO has contractually agreed to waive the Portfolio’s advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Portfolio II Ltd. (the “GMAA Subsidiary”) to PIMCO. The GMAA Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO’s contract with the GMAA Subsidiary is in place.
4
“Other Expenses” and Acquired Fund Fees and Expenses include interest expense of the Portfolio and of the Underlying PIMCO Funds of 0.02% and 0.02%, respectively. Interest expense is borne by the Portfolio and the Underlying PIMCO Funds separately from the management fees paid to PIMCO. Excluding interest expense of the Portfolio and of the Underlying PIMCO Funds, Total Annual Portfolio Operating Expenses After Fee Waiver and/or Expense Reimbursement are 0.95% for Institutional Class shares.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of
investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$101
$358
$635
$1,425
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 360% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio is intended for investors who prefer to have their asset allocation decisions made by professional investment managers. PIMCO uses a three-step approach in seeking to achieve the Portfolio’s investment objective which consists of 1) developing a target asset allocation; 2) developing a series of relative value strategies designed to add value beyond the target allocation; and 3) utilizing hedging techniques to manage risks. PIMCO evaluates these three steps and uses varying combinations of Acquired Funds and/or direct investments to implement them within the Portfolio. The Portfolio may invest in Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end investment companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management (“Underlying PIMCO Funds”), and may also invest in other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds (collectively, “Acquired Funds”).
The Portfolio seeks to achieve its investment objective by investing under normal circumstances in a combination of affiliated and unaffiliated funds, which may or may not be registered under the Investment Company Act of 1940, as amended (the “1940 Act”), Fixed Income Instruments, equity securities, forwards and derivatives. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio will invest in Acquired Funds, securities, instruments and other investments to the extent permitted under the 1940 Act, or any exemptive relief therefrom. To the extent the Portfolio invests in Underlying PIMCO Funds, PIMCO expects to select such Underlying PIMCO Funds without considering or canvassing the universe of available unaffiliated Acquired Funds. The Portfolio will

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

invest either directly or indirectly (through a fund) in instruments that are economically tied to at least three countries (one of which may be the United States).
The Portfolio seeks concurrent exposure to a broad spectrum of asset classes and other investments. The Portfolio will typically invest 50% to 70%, and under normal circumstances will invest a minimum of 20%, of its net assets in equity-related investments (including investment in common stock, preferred securities, equity securities of real estate investment trusts and/or investment in the Domestic Equity-Related Underlying PIMCO Funds, the International Equity-Related Underlying PIMCO Funds and the PIMCO RealEstateRealReturn Strategy Fund, an Underlying PIMCO Fund and in other equity-related Acquired Funds). The Portfolio may invest up to 5% of its net assets in real estate investment trusts. With respect to its direct or indirect (through a fund) investments in equity securities, there is no limitation on the market capitalization range of the issuers in which the Portfolio may invest. The Portfolio may invest up to 5% of its net assets in commodity-related investments (including exposure to commodity-related investments obtained through investment in the PIMCO Cayman Commodity Portfolio II Ltd., a wholly-owned subsidiary of the Portfolio organized under the laws of the Cayman Islands (the “GMAA Subsidiary”), and investment in the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, Underlying PIMCO Funds). The GMAA Subsidiary is advised by PIMCO and primarily invests in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments. As discussed in greater detail elsewhere in this prospectus, the GMAA Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity-linked derivative instruments. The Portfolio may invest up to 25% of its total assets in the GMAA Subsidiary. The Portfolio may invest up to 10% of its net assets in equity securities that are economically tied to emerging market countries. The Portfolio’s combined investments in equity securities tied to emerging market countries, commodity-related investments and real estate investment trusts will normally not exceed 15% of its net assets.
The Portfolio may invest up to 30% of its total assets in Fixed Income Instruments denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 15% of its total assets in Fixed Income Instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other Fixed Income Instruments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The average portfolio duration of this Portfolio normally varies from 0-6 years. Duration is a measure used to
determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio may purchase and sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales.
The Portfolio’s assets are not allocated according to a predetermined blend of shares of the Acquired Funds and/or direct investments in securities, instruments and other investments. Instead, when making allocation decisions among the Acquired Funds, securities, instruments and other investments, PIMCO considers various qualitative and quantitative factors relating to the U.S. and non-U.S. economies, and securities and commodities markets. These factors include projected growth trends in the U.S. and non-U.S. economies, forecasts for interest rates and the relationship between short- and long-term interest rates (yield curve), current and projected trends in inflation, relative valuation levels in the equity, fixed income, commodity and real estate markets and various segments within those markets, the outlook and projected growth of various industrial sectors, information relating to business cycles, borrowing needs and the cost of capital, political trends data relating to trade balances, and labor information. PIMCO uses these factors to help determine the Portfolio’s target asset allocation and to identify potentially attractive relative value and risk hedging strategies. PIMCO has the flexibility to reallocate the Portfolio’s assets among any or all of the investment exposures represented by affiliated or unaffiliated funds, or invest directly in securities, instruments and other investments, based on its ongoing analyses of the global economy and financial markets. While these analyses are performed daily, material shifts in investment exposures typically take place over longer periods of time.
As part of its investment process, PIMCO will seek to reduce exposure to certain risks by implementing various hedging transactions.
Once the target asset allocation, relative value strategies and risk hedging strategies have been determined, PIMCO then evaluates various combinations of affiliated or unaffiliated funds, securities, instruments and other investments to obtain the desired exposures and invests accordingly.
Additional information for these Underlying PIMCO Funds can be found in the Statement of Additional Information and the Underlying PIMCO Funds’ prospectuses and financial reports. Additional Underlying PIMCO Funds may be added or deleted in the future without shareholder notification.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio include risks from direct investments and/ or indirect exposure through investment in Acquired Funds. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are:
Allocation Risk:the risk that a Portfolio could lose money as a result of less than optimal or poor asset allocation decisions. The Portfolio could miss attractive investment opportunities by underweighting

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PIMCO Global Managed Asset Allocation Portfolio

markets that subsequently experience significant returns and could lose value by overweighting markets that subsequently experience significant declines
Acquired Fund Risk:the risk that a Portfolio's performance is closely related to the risks associated with the securities and other investments held by the Acquired Funds and that the ability of a Portfolio to achieve its investment objective will depend upon the ability of the Acquired Funds to achieve their investment objectives
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Distressed Company Risk:the risk that securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the
lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Commodity Risk:the risk that investing in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of

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Prospectus

portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Real Estate Risk:the risk that the Portfolio’s investments in Real Estate Investment Trusts (“REITs”) or real estate-linked derivative instruments will subject the Portfolio to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. A Portfolio’s investments in REITs or real estate-linked derivative instruments subject it to management and tax risks. In addition, privately traded REITs subject a Portfolio to liquidity and valuation risk
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Smaller Company Risk:the risk that the value of securities issued by a smaller company may go up or down, sometimes rapidly and unpredictably as compared to more widely held securities, due to narrow markets and limited resources of smaller companies. A Portfolio’s investments in smaller companies subject it to greater levels of credit, market and issuer risk
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Tax Risk:the risk that the tax treatment of swap agreements and other derivative instruments, such as commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures, may be affected by future regulatory or legislative changes that could affect whether income from such investments is “qualifying income” under Subchapter M of the Internal Revenue Code, or otherwise affect the character, timing and/or amount of the Portfolio’s taxable income or gains and distributions
Subsidiary Risk:the risk that, by investing in the GMAA Subsidiary, the Portfolio is indirectly exposed to the risks associated with the GMAA Subsidiary’s investments. The GMAA Subsidiary is not registered under the 1940 Act and may not be subject to all the investor protections of the 1940 Act. There is no guarantee that the investment objective of the GMAA Subsidiary will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Value Investing Risk:a value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
Exchange-Traded Fund Risk:the risk that an exchange-traded fund may not track the performance of the index it is designed to track, among other reasons, because of exchange rules, market prices of shares of an exchange-traded fund may fluctuate rapidly and materially, or shares of an exchange-traded fund may trade significantly above or below net asset value, any of which may cause losses to the Portfolio invested in the exchange-traded fund
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.

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PIMCO Global Managed Asset Allocation Portfolio

Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The 60% MSCI World Index/40% Bloomberg Barclays U.S. Aggregate Index is a blended index. The MSCI World Index is a free float-adjusted market capitalization weighted index that is designed to measure the equity market performance of developed markets. The MSCI World Index consists of 23 developed market country indices. The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable, and dollar denominated. The Bloomberg Barclays U.S. Aggregate Index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class
Best Quarter
June 30, 2020
15.83%
Worst Quarter
March 31, 2020
-13.96%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Institutional Class Return
17.01%
9.10%
5.17%
4/30/2012
60% MSCI World Index/40%
Bloomberg Barclays U.S. Aggregate
Index (reflects no deductions for fees,
expenses or taxes)
13.31%
9.34%
8.10%
 
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Erin Browne, Geraldine Sundstrom and Emmanuel Sharef. Ms. Browne is a Managing Director of PIMCO and a senior portfolio manager in the Asset Allocation team and has managed the Portfolio since January 2019. Ms. Sundstrom is a Managing Director of PIMCO and a senior portfolio manager in the Asset Allocation team and has managed the Portfolio since July 2015. Dr. Sharef is an Executive Vice President of PIMCO and has managed the Portfolio since December 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

5  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
As the Portfolio may invest in shares of Acquired Funds, including the Underlying PIMCO Funds, the risks of investing in the Portfolio may be closely related to the risks associated with the Acquired Funds, including Underlying PIMCO Funds, and their investments. However, as the Portfolio may also invest its assets directly in stocks or bonds of other issuers and in other instruments, such as forwards, options, futures contracts or swap agreements, the Portfolio may be directly exposed to certain risks described below. As such, unless stated otherwise, any reference in this section to “Portfolios” includes both the Portfolio and Acquired Funds. Where necessary in this section, the Portfolio is specifically referred to as the “Portfolio.”
Allocation Risk
The Portfolio’s investment performance depends upon how its assets are allocated and reallocated according to the Portfolio’s asset allocation targets and ranges. A principal risk of investing in the Portfolio is that PIMCO will make less than optimal or poor asset allocation decisions. PIMCO attempts to identify investment allocations that will provide consistent, quality performance for the Portfolio, but there is no guarantee that such allocation techniques will produce the desired results. It is possible that PIMCO will focus on an investment that performs poorly or underperforms other investments under various market conditions. You could lose money on your investment in the Portfolio as a result of these allocation decisions.
Acquired Fund Risk
Because the Portfolio may invest its assets in Acquired Funds, the risks associated with investing in the Portfolio may be closely related to the risks associated with the securities and other investments held by the Acquired Funds. The ability of the Portfolio to achieve its investment objective may depend upon the ability of the Acquired Funds to achieve their respective investment objectives. There can be no assurance that the investment objective of any Acquired Fund will be achieved.
The Portfolio’s net asset value (“NAV”) will fluctuate in response to changes in the NAVs of the Acquired Funds in which it invests. The extent to which the investment performance and risks associated with the Portfolio correlates to those of a particular Acquired Fund will depend upon the extent to which the Portfolio’s assets are allocated from time to time for investment in the Acquired Fund, which may vary. As discussed under “Description of Principal Risks—Market Risk,” because the NAV of the Portfolio is related to the NAVs of the Acquired Funds in which it invests, inaccuracies, delays or other disruptions in the calculation of an Acquired Fund’s NAV may adversely impact the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the NAV of the Portfolio’s shares.

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Prospectus

A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the

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PIMCO Variable Insurance Trust

Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Distressed Company Risk
The Portfolio’s investments in securities of distressed companies may be subject to greater levels of credit, issuer and liquidity risk than a portfolio that does not invest in such securities. Securities of distressed companies include both debt and equity securities. Debt securities of distressed companies are considered predominantly speculative with respect to the issuers’ continuing ability to make principal and interest payments. Issuers of distressed company securities may also be involved in restructurings or bankruptcy proceedings that may not be successful. An economic downturn or period of rising interest rates could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities (liquidity risk). If the issuer of a debt security is in default with respect to interest or principal payments, the Portfolio may lose its entire investment.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio and certain Acquired Funds may rely on various third-party sources to calculate its NAV. As a result, the Portfolio and such Acquired Funds are subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s and Acquired Funds' calculations of their NAVs, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. Also, because the NAV of the Portfolio is related to the NAVs of the Acquired Funds in which it invests, the Portfolio may be adversely impacted by such inaccuracies, delays or other disruptions in the calculation of an Acquired Fund's NAV. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate,

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credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests. These factors include the possibility that the Portfolio's commodity derivatives positions may have different roll dates, reset dates or contract months than those specified in a particular commodity index.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio

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to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Commodity Risk
The Portfolio’s investments in commodity-linked derivative instruments may subject the Portfolio to greater volatility than investments in traditional securities. The value of commodity-linked derivative instruments may be affected by changes in overall market movements, commodity index volatility, changes in interest rates, or factors affecting a particular industry or commodity, such as drought, floods, weather, livestock disease, public health emergencies, embargoes, tariffs and international economic, political and regulatory developments. The GMAA Subsidiary and certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, may each concentrate its assets in a particular sector of the commodities market (such as oil, metal or agricultural products). As a result, the GMAA Subsidiary and certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, and, to the extent the Portfolio invests in the GMAA Subsidiary and/or certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, the Portfolio may be more susceptible to risks associated with those sectors. The prices for commodities in those sectors may fluctuate widely due to factors such as changes in value, supply and demand and governmental regulatory policies.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets

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in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Real Estate Risk
Investments in real estate investment trusts (“REITs”) or real estate-linked derivative instruments are subject to risks similar to those associated with direct ownership of real estate, including losses from casualty or condemnation, and changes in local and general economic conditions, supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. An investment in a REIT or a real estate-linked derivative instrument that is linked to the value of a REIT is subject to additional risks, such as poor performance by the manager of the REIT, adverse changes to the tax laws or failure by the REIT to qualify for tax-free pass-through of income under the Internal Revenue Code of 1986, as amended (the “Code”). In addition, some REITs have limited diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Also, the organizational documents of a REIT may contain provisions that make changes in control of the REIT difficult and time-consuming. Finally, private REITs are not traded on a national securities exchange. As such, these products are generally illiquid. This reduces the ability of a Portfolio to redeem its investment early. Private REITs are also generally harder to value and may bear higher fees than public REITs.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leverage risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The GMAA Subsidiary will comply with these asset segregation or “earmarking” requirements to the same extent as the Portfolio. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy its obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities (or the value of the Acquired Funds). Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Smaller Company Risk
The general risks associated with fixed income securities and equity securities are particularly pronounced for securities issued by companies with smaller market capitalizations. These companies may have limited product lines, markets or financial resources or they may depend on a few key employees. As a result, they may be subject to greater levels of credit, market and issuer risk. Securities of smaller companies may trade less frequently and in lesser volumes than more widely held securities and their values may fluctuate more sharply than other securities. Companies with medium-sized market capitalizations may have risks similar to those of smaller companies.
Management Risk
The Portfolio, the GMAA Subsidiary and certain Acquired Funds are subject to management risk because they are actively managed investment portfolios. PIMCO or the sub-adviser, as applicable, or in the case of a fund that is not managed by PIMCO, such other fund’s investment adviser and sub-adviser, as applicable, and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, the GMAA Subsidiary and the Acquired Funds, as applicable, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio or an Acquired Fund seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio or Acquired Fund. To the extent the Portfolio or Acquired Fund employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio or Acquired Fund. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in

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value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Because a number of Underlying PIMCO Funds obtain exposure to certain proprietary model stock portfolios by investing in equity total return swaps based on such model portfolios, in other securities and instruments to replicate the performance of such model portfolios, or directly in the equity securities held in such model portfolios, such Underlying PIMCO Funds will be subject to the risks associated with the management of these proprietary model stock portfolios by the sub-adviser to such Underlying PIMCO Funds.
Tax Risk
The Portfolio and certain Underlying PIMCO Funds, including the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, gain exposure to the commodities markets through investments in commodity-linked derivative instruments, including commodity index-linked notes, swap agreements, commodity options, futures, and options on futures. The Portfolio may also gain exposure indirectly to commodity markets by investing in the GMAA Subsidiary, which invests primarily in commodity-linked derivative instruments backed by a portfolio of inflation-indexed securities and/or other Fixed Income Instruments. In order for the Portfolio to qualify as a regulated investment company under Subchapter M of the Internal Revenue Code of 1986, as amended (the “Code”), the Portfolio must derive at least 90 percent of its gross income each taxable year from certain qualifying sources of income.
As more fully described below under “Tax Consequences-A Note on the Portfolio,” the Internal Revenue Service (the “IRS”) issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. The IRS has issued private letter rulings in which the IRS specifically concluded that income derived from an investment in a subsidiary will also constitute qualifying income to the Portfolio. Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio‘s income from an investment in the subsidiary distributed annually or is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the Investment Company Act of 1940, as amended (the “1940 Act”).
The Portfolio will seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the GMAA Subsidiary. If the IRS were to determine that income derived from certain commodity-linked notes or from investments in the GMAA Subsidiary does not constitute qualifying income, the Portfolio and certain Underlying PIMCO Funds, including the PIMCO CommodityRealReturn Strategy Fund® and PIMCO CommoditiesPLUS® Strategy Fund, might be adversely affected and would be required to reduce their exposure to such investments which might result in difficulty in implementing their investment strategies and increased costs and taxes.
The use of commodity index-linked notes and investments in the GMAA Subsidiary involve specific risks. See “Characteristics and Risks of Securities and Investment Techniques-Derivatives-A Note on the Portfolio” below for further information regarding commodity index-linked notes, including the risks associated with these instruments. In addition, see “Characteristics and Risks of Securities and Investment Techniques-Investments in the Wholly-Owned Subsidiary” below for further information regarding the GMAA Subsidiary, including the risks associated with investing in the GMAA Subsidiary.
Subsidiary Risk
By investing in the GMAA Subsidiary, the Portfolio is indirectly exposed to the risks associated with the GMAA Subsidiary’s investments. The investments held by the GMAA Subsidiary are generally similar to those that are permitted to be held by the Portfolio and are subject to the same risks that apply to similar investments if held directly by the Portfolio. These risks are described elsewhere in this prospectus. There can be no assurance that the investment objective of the Portfolio or the GMAA Subsidiary will be achieved.
The GMAA Subsidiary is not registered under the 1940 Act, and, unless otherwise noted in this prospectus, is not subject to all the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the GMAA Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the GMAA Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased

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during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Value Investing Risk
Value investing attempts to identify companies that are believed to be undervalued. Value stocks typically have prices that are low relative to factors such as the company’s earnings, cash flow or dividends. A value stock may decrease in price or may not increase in price as anticipated by PIMCO if it continues to be undervalued by the market or the factors that the portfolio manager believes will cause the stock price to increase do not occur. A value investing style may perform better or worse than equity portfolios that focus on growth stocks or that have a broader investment style.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.
Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
Exchange-Traded Fund (“ETF”) Risk
Investments in ETFs entail certain risks. Investments in ETFs designed to track an index involve the risk that the ETF’s performance may not track the performance of the index the ETF is designed to track. This deviation may occur due to cash inflows and outflows from and to investors buying and redeeming shares or due to occasional differences between the composition of the index and the securities held by the ETF. In addition, investments in ETFs involve the risk that the market prices of ETF shares will fluctuate, sometimes rapidly and materially, in response to changes in the ETF’s NAV, the value of ETF holdings and supply and demand for ETF shares. Although ETFs will generally trade close to NAV, market volatility, lack of an active trading market for ETF shares, disruptions at market participants (such as Authorized Participants or market makers) and any disruptions in the ordinary functioning of the creation/redemption process may result in ETF shares trading significantly above (at a “premium”) or below (at a “discount”) NAV. Significant losses may result when transacting in ETF shares in these and other circumstances.

April 30, 2021 | PROSPECTUS  15

PIMCO Variable Insurance Trust

LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

16  Prospectus | PIMCO Variable Insurance Trust

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters. PIMCO also serves as the investment adviser for the GMAA Subsidiary.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.95% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.90% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
As discussed in the “Portfolio Summary-Principal Investment Strategies” section, the Portfolio may pursue its investment objective by investing in the GMAA Subsidiary. The GMAA Subsidiary has entered into a separate contract with PIMCO whereby PIMCO provides investment advisory and other services to the GMAA Subsidiary. In consideration of these services, the GMAA Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. PIMCO has contractually agreed to waive the advisory fee and the supervisory and administrative fee it receives from the Portfolio in an amount equal to the management fee and administrative services fee, respectively, paid to PIMCO by the GMAA Subsidiary. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO’s contract with the GMAA Subsidiary is in place.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees at the annual rate of 0.05% for
Institutional Class shares (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not:

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Fund of Funds Fees
The Portfolio is permitted to invest in Underlying PIMCO Funds, which, for the Portfolio, is defined to include Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. The Portfolio is further permitted to invest in Acquired Funds, which, for the Portfolio, is defined to include the Underlying PIMCO Funds and other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds, which may or may not be registered under the 1940 Act.
The Portfolio pays advisory and supervisory and administrative fees directly to PIMCO at an annual rate stated above, based on the average daily net assets attributable in the aggregate to the Portfolio’s Institutional Class shares. The Portfolio also indirectly pays its proportionate share of the advisory, supervisory and administrative and management fees charged by PIMCO to the Underlying PIMCO Funds and, to the extent not included among the Underlying PIMCO Funds, funds of PIMCO ETF Trust in which the Portfolio invests (collectively, “Underlying PIMCO Fund Fees”).
PIMCO has contractually agreed, through May 1, 2022, to waive, first, the advisory fee and, second, to the extent necessary, the supervisory and administrative fee it receives from the Portfolio in an amount equal to the Underlying PIMCO Fund Fees indirectly incurred by the Portfolio in connection with its investments in Underlying PIMCO Funds (for purposes of this expense reduction, this term includes funds of PIMCO ETF Trust), to the extent the Portfolio’s advisory fee or advisory fee and supervisory and administrative fee, taken together, are greater than or equal to the Underlying PIMCO Fund Fees. This waiver will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term.
The Acquired Fund Fees and Expenses shown in the Annual Portfolio Operating Expenses table may be higher than the Underlying PIMCO Fund Fees used for purposes of the Expense Reduction shown in that table due to differences in the methods of calculation. The Acquired Fund Fees and Expenses, as required to be shown in the Annual Portfolio Operating Expenses table, are calculated using the total operating expenses for each Underlying PIMCO Fund (and any unaffiliated funds) over the Portfolio’s average net assets. The Underlying PIMCO Fund Fees that are used for purposes of implementing the expense reduction described above are calculated using the advisory and supervisory and administrative fees for each Underlying PIMCO Fund over the total assets invested in Underlying PIMCO Funds. Thus, the Acquired Fund Fees and Expenses listed in the Annual Portfolio Operating Expenses table will typically be higher than the Underlying PIMCO Fund Fees used to calculate the Expense Reduction when the Portfolio employs leverage as an investment strategy.
The expenses associated with investing in a fund of funds are generally higher than those for mutual funds that do not invest in other funds. The cost of investing in the Portfolio will generally be higher than the cost of investing in a Portfolio that invests directly in individual stocks and bonds. By investing in the Portfolio, an investor will indirectly bear fees and expenses charged by non-PIMCO Acquired Funds (and may indirectly bear a portion of the fees and expenses charged by Underlying PIMCO Funds to the extent such fees and expenses are not waived or reimbursed pursuant to applicable waiver and reimbursement agreements) in addition to the Portfolio’s direct fees and expenses. In addition, the use of a fund of funds structure could affect the timing, amount and character of distributions to shareholders and may therefore increase the amount of taxes payable by shareholders. The Portfolio, to the extent it invests in Underlying PIMCO Funds, invests in Institutional Class or Class M shares of the Underlying PIMCO Funds, which are not subject to any sales charges or distribution (12b-1) fees.
The following table summarizes the annual expenses borne by Institutional Class or Class M shareholders of the Underlying PIMCO Funds (or, in the case of those operating as exchange-traded funds, the Underlying PIMCO Fund shareholders). Because the Portfolio, to the extent it invests in Underlying PIMCO Funds, invests in Institutional Class or Class M shares of the Underlying PIMCO Funds, shareholders of the Portfolio would indirectly bear a proportionate share of these expenses, depending upon how the Portfolio’s assets are allocated from time to time among the Underlying PIMCO Funds.
For a complete description of an Underlying PIMCO Fund, please see the Underlying PIMCO Fund’s prospectus or offering memorandum, as applicable. For a summary description of the Underlying PIMCO Funds, please see the “Descriptions of the Underlying PIMCO Funds” section in this prospectus.
Annual Underlying PIMCO Fund Expenses
(Based on the average daily net assets attributable to an Underlying PIMCO Fund’s Institutional Class shares (or Class M shares in the case of the PIMCO Government Money Market Fund )).

April 30, 2021 | PROSPECTUS  19

PIMCO Variable Insurance Trust

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO California Intermediate Municipal Bond Fund
0.445%
0.00%
0.445%
PIMCO California Municipal Bond Fund
0.44%
0.02%
0.46%
PIMCO California Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Climate Bond Fund
0.50%
0.00%
0.50%
PIMCO CommoditiesPLUS® Strategy Fund
0.74%
0.27%
1.01%(3)
PIMCO CommodityRealReturn Strategy Fund®
0.74%
0.76%
1.50%(4)
PIMCO Credit Opportunities Bond Fund
0.90%
0.02%
0.92%
PIMCO Diversified Income Fund
0.75%
0.04%
0.79%
PIMCO Dividend and Income Fund
0.75%
0.05%
0.80%(5)
PIMCO Dynamic Bond Fund
0.80%
0.05%
0.85%
PIMCO Emerging Markets Bond Fund
0.83%
0.05%
0.88%
PIMCO Emerging Markets Corporate Bond Fund
0.90%
0.12%
1.02%
PIMCO Emerging Markets Currency and Short-Term Investments Fund
0.85%
0.03%
0.88%
PIMCO Emerging Markets Local Currency and Bond Fund
0.90%
0.80%
1.70%
PIMCO ESG Income Fund
0.50%
0.07%
0.57%(6)
PIMCO Extended Duration Fund
0.50%
1.21%
1.71%
PIMCO Global Advantage® Strategy Bond Fund
0.65%
0.21%
0.86%
PIMCO Global Bond Opportunities Fund (U.S. Dollar-Hedged)
0.55%
0.04%
0.59%
PIMCO Global Bond Opportunities Fund (Unhedged)
0.55%
0.12%
0.67%
PIMCO GNMA and Government Securities Fund
0.50%
0.33%
0.83%
PIMCO Government Money Market Fund
0.18%
0.00%
0.18%(7)
PIMCO High Yield Fund
0.55%
0.02%
0.57%
PIMCO High Yield Municipal Bond Fund
0.55%
0.08%
0.63%
PIMCO High Yield Spectrum Fund
0.60%
0.02%
0.62%
PIMCO Income Fund
0.50%
0.59%
1.09%
PIMCO International Bond Fund (U.S. Dollar-Hedged)
0.50%
0.10%
0.60%
PIMCO International Bond Fund (Unhedged)
0.50%
0.13%
0.63%
PIMCO Investment Grade Credit Bond Fund
0.50%
0.35%
0.85%
PIMCO Long Duration Total Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term Credit Bond Fund
0.55%
0.29%
0.84%
PIMCO Long-Term Real Return Fund
0.50%
0.57%
1.07%
PIMCO Long-Term U.S. Government Fund
0.475%
1.38%
1.855%
PIMCO Low Duration Credit Fund(8)
0.70%
0.05%
0.75%
PIMCO Low Duration ESG Fund
0.50%
0.08%
0.58%
PIMCO Low Duration Fund
0.46%
0.41%
0.87%
PIMCO Low Duration Fund II
0.50%
0.03%
0.53%
PIMCO Low Duration Income Fund
0.50%
0.05%
0.55%
PIMCO Moderate Duration Fund
0.46%
0.15%
0.61%
PIMCO Mortgage Opportunities and Bond Fund
0.60%
1.22%
1.82%
PIMCO Mortgage-Backed Securities Fund
0.50%
0.25%
0.75%
PIMCO Municipal Bond Fund
0.44%
0.07%
0.51%
PIMCO National Intermediate Municipal Bond Fund
0.45%
0.00%
0.45%
PIMCO New York Municipal Bond Fund
0.445%
0.05%
0.495%
PIMCO Preferred and Capital Securities Fund
0.79%
0.09%
0.88%(9)
PIMCO RAE Emerging Markets Fund
0.75%
0.02%
0.77%(10)
PIMCO RAE Fundamental Advantage PLUS Fund
0.89%
0.07%
0.96%
PIMCO RAE International Fund
0.50%
0.02%
0.52%(5)
PIMCO RAE PLUS EMG Fund
1.10%
0.21%
1.31%
PIMCO RAE PLUS Fund
0.79%
0.08%
0.87%
PIMCO RAE PLUS International Fund
0.82%
0.05%
0.87%
PIMCO RAE PLUS Small Fund
0.84%
0.09%
0.93%
PIMCO RAE US Fund
0.40%
0.02%
0.42%(5)

20  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Underlying PIMCO Fund
Management
Fees(1)
Other
Expenses(2)
Total Annual Fund
Operating Expenses
PIMCO RAE US Small Fund
0.50%
0.04%
0.54%
PIMCO RAE Worldwide Long/Short PLUS Fund
1.19%
0.09%
1.28%
PIMCO Real Return Fund
0.45%
0.08%
0.53%
PIMCO RealEstateRealReturn Strategy Fund
0.74%
1.36%
2.10%
PIMCO Short Asset Investment Fund
0.34%
0.02%
0.36%
PIMCO Short Duration Municipal Income Fund
0.33%
0.00%
0.33%
PIMCO Short-Term Fund
0.45%
0.10%
0.55%
PIMCO StocksPLUS® Absolute Return Fund
0.64%
0.08%
0.72%
PIMCO StocksPLUS® Fund
0.50%
0.06%
0.56%
PIMCO StocksPLUS® International Fund (U.S. Dollar-Hedged)
0.75%
0.25%
1.00%
PIMCO StocksPLUS® International Fund (Unhedged)
0.64%
0.38%
1.02%
PIMCO StocksPLUS® Long Duration Fund
0.59%
0.42%
1.01%
PIMCO StocksPLUS® Short Fund
0.64%
0.45%
1.09%
PIMCO StocksPLUS® Small Fund
0.69%
0.06%
0.75%
PIMCO Strategic Bond Fund
0.55%
0.02%
0.57%(11)
PIMCO Total Return ESG Fund
0.50%
0.46%
0.96%
PIMCO Total Return Fund
0.46%
0.24%
0.70%
PIMCO Total Return Fund II
0.50%
0.26%
0.76%
PIMCO Total Return Fund IV
0.50%
0.30%
0.80%
PIMCO TRENDS Managed Futures Strategy Fund
1.40%
0.29%
1.69%(12)
1
“Management Fees” reflects an advisory fee and a supervisory and administrative fee payable by an Underlying PIMCO Fund to PIMCO.
2
Other Expenses include expenses such as organizational expenses, interest expense, taxes, governmental fees, pro rata Trustees' fees and acquired fund fees and expenses attributable to the Institutional Class or Class M shares or the Fund in the case of exchange-traded funds of the PIMCO ETF Trust or PIMCO Equity Series.
3
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund III Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
4
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund I Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
5
PIMCO has contractually agreed, through October 31, 2021, to waive a portion of the Fund's supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund's organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to PIMCO Equity Series at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
6
PIMCO has contractually agreed, through July 31, 2022, to waive a portion of the Fund’s supervisory and administrative fees, or reimburse the Fund, to the extent that the Fund’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). This Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the investment advisory contract or supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Fund of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that certain conditions are met.
7
To maintain certain net yields for the Fund, PIMCO or its affiliates may temporarily and voluntarily waive, reduce or reimburse all or any portion of the Fund's fees and expenses.
8
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund.
9
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Capital Securities Fund (Cayman) Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
10
PIMCO has contractually agreed, through July 31, 2022, to reduce its supervisory and administrative fee for each share class of the Fund by 0.05% of the average daily net assets attributable to the applicable class of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years from the date of waiver.
11
PIMCO has contractually agreed, through July 31, 2022, to reduce its advisory fee by 0.10% of the average daily net assets of the Fund. This Fee Waiver Agreement renews annually unless terminated by PIMCO upon at least 30 days' prior notice to the end of the contract term. Under certain conditions, PIMCO may recoup amounts reduced in future periods, not exceeding three years.

April 30, 2021 | PROSPECTUS  21

PIMCO Variable Insurance Trust

12
PIMCO has contractually agreed to waive the Fund's advisory fee and the supervisory and administrative fee in an amount equal to the management fee and administrative services fee, respectively, paid by the PIMCO Cayman Commodity Fund VIII, Ltd. (the “Subsidiary”) to PIMCO. The Subsidiary pays PIMCO a management fee and an administrative services fee at the annual rates of 0.49% and 0.20%, respectively, of its net assets. This waiver may not be terminated by PIMCO and will remain in effect for as long as PIMCO's contract with the Subsidiary is in place.
Individual Portfolio Managers
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Global Managed Asset Allocation
Erin Browne
1/19
Managing Director, PIMCO. Ms. Browne is a portfolio manager in the Newport Beach office,
focusing on multi-asset strategies. In her role, she works with PIMCO's asset allocation team
and with portfolio managers across asset classes and sectors globally. Prior to joining
PIMCO in 2018, Ms. Browne was a managing director and head of asset allocation at UBS
Asset Management, helping to drive the firm's macro research, capital market assumptions,
tactical asset allocation and strategic asset allocation views across asset classes. Previously,
she was head of macro investments at UBS O'Connor, a multi-strategy hedge fund manager,
and a global macro portfolio manager at Point72 Asset Management. Ms. Browne has also
held roles at Citigroup, Moore Capital Management and Neuberger Berman, and she began
her career at Lehman Brothers. She has investment experience since 2002 and holds a
bachelor's degree in economics from Georgetown University.
PIMCO Global Managed Asset Allocation
Emmanuel Sharef
12/19
Executive Vice President, PIMCO. Dr. Sharef is an executive vice president and portfolio
manager in the Newport Beach office, focused on asset allocation strategies and the
residential real estate market. He is a member of the Americas Portfolio Committee and has
served as a rotating member of the Investment Committee. Prior to joining PIMCO in 2011,
he worked in the mortgage credit strategists group at Morgan Stanley. He has investment
and financial services experience since 2008 and holds a Ph.D. in operations research from
Cornell University, specializing in statistics and biometrics. He received an undergraduate
degree from Princeton University.
PIMCO Global Managed Asset Allocation
Geraldine Sundstrom
7/15
Managing Director, PIMCO. Ms. Sundstrom is a portfolio manager in the London office,
focusing on asset allocation strategies. Prior to joining PIMCO in 2015, she was a partner
and portfolio manager at Brevan Howard, where she led the Emerging Markets Strategies
Fund. Previously, she was a portfolio manager at Moore Capital Management. She has
investment experience since 1996 and holds a master's degree in finance from Birkbeck
College at London University and two degrees from Universite Paris Dauphine.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

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Prospectus

From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

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Prospectus

investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
A Note on the Portfolio. One of the requirements for favorable tax treatment as a regulated investment company under the Code is that the Portfolio derives at least 90% of its gross income from certain qualifying sources of income. The IRS has issued a revenue ruling which holds that income derived from commodity-linked swaps is not qualifying income under Subchapter M of the Code. As such, the Portfolio’s ability to utilize commodity-linked swaps as part of its investment strategy is limited to a maximum of 10% of its gross income.
However, in a subsequent revenue ruling, the IRS provides that income from alternative investment instruments (such as certain commodity index-linked notes) that create commodity exposure may be considered qualifying income under the Code. The IRS has also issued private letter

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rulings in which the IRS specifically concluded that income from certain commodity index-linked notes is qualifying income (collectively, the “Notes Rulings”). In addition, the IRS has also issued private letter rulings in which the IRS specifically concluded that income derived from an investment in a subsidiary will also constitute qualifying income, even if that subsidiary itself owns commodity-linked swaps. The Portfolio will continue to seek to gain exposure to the commodity markets primarily through investments in commodity index-linked notes and through investments in the GMAA Subsidiary.
Under IRS regulations, income derived from a controlled foreign corporation will be considered qualifying income if the Portfolio‘s income from an investment in the subsidiary is derived with respect to the Portfolio’s business of investing in securities. An IRS revenue procedure states that the IRS will not in the future issue private letter rulings that would require a determination of whether an asset (such as a commodity index-linked note) is a “security” under the 1940 Act. In connection with issuing such revenue procedure, the IRS has revoked the Notes Rulings. There can be no assurance that the IRS will not change its position with respect to some or all of these conclusions or that future legislation will not adversely impact the tax treatment of the Portfolio’s commodity-linked investments. If the IRS were to change or reverse its position, or if future legislation adversely affected the tax treatment of the Portfolio’s commodity-linked investments, there would likely be a significant adverse impact on the Portfolio, including the possibility of failing to qualify as a regulated investment company. If the Portfolio did not qualify as a regulated investment company for any taxable year, its taxable income would be subject to tax at the Portfolio level at regular corporate tax rates (without reduction for distributions to shareholders) and to a further tax at the shareholder level when such income is distributed. Furthermore, the tax treatment of commodity-linked notes, other commodity-linked derivatives, and the Portfolio’s investments in the GMAA Subsidiary may otherwise be adversely affected by future legislation, court decisions, Treasury Regulations and/or guidance issued by the IRS. Such developments could affect the character, timing and/or amount of the Portfolio’s taxable income or any distribution made by the Portfolio or result in the inability of the Portfolio to operate as described in this Prospectus.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
As the Portfolio may invest in shares of the Acquired Funds, the risks of investing in the Portfolio may be closely related to the risks associated with the Acquired Funds and their investments. However, as the Portfolio may also invest its assets directly in Fixed Income Instruments, equity securities, forwards or derivatives, such as options, futures
contracts or swap agreements, other affiliated or unaffiliated funds, and other investments, the Portfolio may be directly exposed to certain risks described below.
This section provides additional information about some of the principal investments and related risks of the Portfolio and of certain Acquired Funds described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio and certain Acquired Funds from time to time. Generally, the characteristics and risks of securities and investment techniques that may be used by the Acquired Funds from time to time are similar to those described below. However, the risks associated with an Acquired Fund’s investments are described more fully in each Acquired Fund’s prospectus. Accordingly, please see an Acquired Fund’s prospectus for a more complete description of the Acquired Fund and the risks associated with its investments.
Most of these securities and investment techniques described herein are discretionary, which means that PIMCO, or in the case of a fund that is not managed by PIMCO, such fund’s investment adviser and sub-adviser, as applicable, can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio or Acquired Funds. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Because the Portfolio may invest a portion of its assets in the GMAA Subsidiary, which may hold some of the investments described in this prospectus, the Portfolio may be indirectly exposed to the risks associated with those investments. With respect to its investments, the GMAA Subsidiary will generally be subject to the same fundamental, non- fundamental and certain other investment restrictions as the Portfolio; however, the GMAA Subsidiary (unlike the Portfolio) may invest without limitation in commodity-linked swap agreements and other commodity- linked derivative instruments. The Portfolio and the GMAA Subsidiary may test for compliance with certain investment restrictions on a consolidated basis, except that with respect to their investments in certain securities that may involve leverage, the GMAA Subsidiary will comply with asset segregation or “earmarking” requirements to the same extent as the Portfolio.
Investors should be aware that the investments made by a Portfolio and the results achieved by a Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to a Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact a Portfolio’s portfolio management.

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For example, a Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause Portfolios to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase a Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause a Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect a Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.

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Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal
Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is

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funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity
absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.

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One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore,

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the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds,

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the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and
equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this Prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions. Preferred and other senior

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securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights. Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time. In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
While certain Underlying PIMCO Funds will generally invest in equity derivatives, each such Underlying PIMCO Fund may invest without limit directly in equity securities, including common stocks, preferred securities and convertible securities. In addition, the PIMCO CommoditiesPLUS® Strategy Fund and PIMCO CommodityRealReturn Strategy Fund®, each an Underlying PIMCO Fund, may invest in equity securities of issuers in commodity-related industries, and the PIMCO RealEstateRealReturn Strategy Fund, an Underlying PIMCO Fund, may invest in REITs and equity securities of issuers in real estate-related industries. The Portfolio may also invest directly in equity securities. When investing directly in equity securities, the Portfolio will not be limited to only those equity securities with any particular weighting in the Portfolio’s benchmark index, if any. Generally, the Portfolio may consider investing directly in equity securities when derivatives on the underlying securities appear to be overvalued.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.
The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined

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by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,
PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for

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many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign
currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.

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Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with

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many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or
holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
A Note on the Portfolio. In light of relevant IRS guidance, as discussed above under “Tax Consequences—A Note on the Portfolio,” the Portfolio will seek to gain exposure to the commodity markets primarily through investments in leveraged or unleveraged commodity index-linked notes, which are derivative debt instruments with principal and/or coupon payments linked to the performance of commodity indices, and through investments in the GMAA Subsidiary (as discussed below). The Portfolio may also invest in commodity-linked notes with principal and/or coupon payments linked to the value of particular commodities or commodity futures contracts, or a subset of commodities and commodities futures contracts. These notes are sometimes referred to as “structured notes” because the terms of these notes may be structured by the issuer and the purchaser of the

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note. The value of these notes will rise or fall in response to changes in the underlying commodity, commodity futures contract, subset of commodities, subset of commodities futures contracts or commodity index.
These notes expose the Portfolio economically to movements in commodity prices. These notes also are subject to risks, such as credit, market and interest rate risks, that in general affect the values of debt securities. In addition, these notes are often leveraged, increasing the volatility of each note’s market value relative to changes in the underlying commodity, commodity futures contract or commodity index. Therefore, at the maturity of the note, the Portfolio may receive more or less principal than it originally invested. The Portfolio might receive interest payments on the note that are more or less than the stated coupon interest payments.
The Portfolio may also invest in other commodity-linked derivative instruments, including swap agreements, commodity options, futures and options on futures. The value of a commodity-linked derivative investment generally is based upon the price movements of a physical commodity (such as energy, mineral, or agricultural products), a commodity futures contract, a subset of commodities, a subset of commodities futures contracts or commodity index, or other economic variable based upon changes in the value of commodities or the commodities markets.
Options transactions may be effected on exchanges or in the OTC market. When OTC options are purchased, the Portfolio’s portfolio bears the risk that the counterparty that wrote the option will be unable or unwilling to perform its obligations under the option contract. Options may also be illiquid and, in such cases, the Portfolio may have difficulty closing out its position. OTC options also may include options on baskets of specific securities.
Many swap transactions are privately negotiated agreements between the Portfolio and a counterparty to exchange or swap investment cash flows or assets at specified intervals in the future. The obligations may extend beyond one year. There is often no central exchange for swap transactions and therefore they can be less liquid investments than exchange-traded instruments. The Dodd-Frank Act and related regulatory developments require the clearing and exchange-trading of certain standardized OTC derivative instruments that the CFTC and SEC have defined as “swaps.” The CFTC has implemented mandatory exchange- trading and clearing requirements under the Dodd-Frank Act and the CFTC continues to approve contracts for central clearing. Uncleared swaps are subject to margin requirements that are being implemented on a phased-in basis. The investment adviser will continue to monitor these developments, particularly to the extent regulatory changes affect a Portfolio’s ability to enter into swap agreements.
As described below under “Characteristics and Risks of Securities and Investment Techniques—Investments in the Wholly-Owned Subsidiary,” the Portfolio may gain exposure to commodity markets by investing in the GMAA Subsidiary. It is expected that the GMAA Subsidiary will invest primarily in commodity-linked derivative instruments, including
swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation-indexed securities and other Fixed Income Instruments.
The IRS issued a revenue ruling that limits the extent to which the Portfolio may invest directly in commodity-linked swaps or certain other commodity- linked derivatives. The GMAA Subsidiary, on the other hand, may invest in these commodity-linked derivatives generally without limitation. See “Tax Consequences—A Note on the Portfolio,” above for further information.
Investments in a Wholly Owned Subsidiary
Investments in the GMAA Subsidiary are expected to provide the Portfolio with exposure to the commodity markets within the limitations of Subchapter M of the Code and recent IRS revenue rulings, as discussed above under “Tax Consequences—A Note on the Portfolio.”
It is expected that the GMAA Subsidiary will invest primarily in commodity- linked derivative instruments, including swap agreements, commodity options, futures and options on futures, backed by a portfolio of inflation- indexed securities and other Fixed Income Instruments. Although the Portfolio may enter into these commodity-linked derivative instruments directly, the Portfolio will likely gain exposure to these derivative instruments indirectly by investing in the GMAA Subsidiary. To the extent that PIMCO believes that these commodity-linked derivative instruments are better suited to provide exposure to the commodities market than commodity index-linked notes, the Portfolio’s investment in the GMAA Subsidiary will likely increase. The GMAA Subsidiary will also invest in inflation-indexed securities and/or other Fixed Income Instruments, which are intended to serve as margin or collateral for the GMAA Subsidiary’s derivatives position, common and preferred securities as well as convertible securities of issuers in commodity-related industries, collateralized debt obligations, event-linked bonds and event-linked swaps. To the extent that the Portfolio invests in the GMAA Subsidiary, it may be subject to the risks associated with those derivative instruments and other securities, which are discussed elsewhere in this prospectus.
While the GMAA Subsidiary may be considered similar to an investment company, it is not registered under the 1940 Act and, unless otherwise noted in the prospectus, is not subject to all of the investor protections of the 1940 Act. In addition, changes in the laws of the United States and/or the Cayman Islands could result in the inability of the Portfolio and/or the GMAA Subsidiary to operate as described in this prospectus and the SAI and could adversely affect the Portfolio. Changes in the laws of the United States and/or the Cayman Islands could adversely affect the performance of the Portfolio and/or the GMAA Subsidiary and result in the Portfolio underperforming its benchmark index(es).
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders

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PIMCO Variable Insurance Trust

substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in Underlying PIMCO Funds and, to the extent permitted by the 1940 Act or exemptive relief therefrom, other affiliated and unaffiliated funds, which may or may not be registered under the 1940 Act, such as open-end or closed-end management investment companies, exchange-traded funds and exchange-traded vehicles. Other unaffiliated investment companies are not required to make their shares available for purchase by the Portfolio, and there is no guarantee that such investment will be, or will continue to be, available. Each Underlying PIMCO Fund may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or

42  Prospectus | PIMCO Variable Insurance Trust

Prospectus

other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The limitation described in the foregoing sentence shall not apply to the Portfolio’s investment in the GMAA Subsidiary. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio and each Underlying PIMCO Fund may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act, and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire,
convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities

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PIMCO Variable Insurance Trust

lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. In addition to indirectly bearing the expenses associated with portfolio turnover of the Acquired Funds, the Portfolio will directly bear these expenses to the extent that that it invests in other securities and instruments.  Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objectives of the Portfolio and certain Underlying PIMCO Funds are non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval. The investment objectives of certain Underlying PIMCO Funds are fundamental and may not be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.

44  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, sub-advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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PIMCO Variable Insurance Trust

Descriptions of the Underlying PIMCO Funds
The Portfolio may invest its assets in some or all of the Underlying PIMCO Funds, which for the Portfolio, is defined to include Institutional Class or Class M shares of any funds of the PIMCO Funds and PIMCO Equity Series, affiliated open-end investment companies, except other funds of funds and series of PIMCO Funds sub-advised by Gurtin Municipal Bond Management. The Portfolio is further permitted to invest in Acquired Funds, which, for the Portfolio, is defined to include the Underlying PIMCO Funds and other affiliated, including funds of PIMCO ETF Trust, and unaffiliated funds, which may or may not be registered under the 1940 Act. Because the Underlying PIMCO Funds are not offered in this prospectus, the following provides a general description of the main investments and other information about the Underlying PIMCO Funds. At the discretion of PIMCO and without shareholder approval, the Portfolio may invest in additional Underlying PIMCO Funds created in the future. For a complete description of an Underlying PIMCO Fund, please see that Fund’s Institutional Class or Class M prospectus, which is incorporated herein by reference and is available free of charge by telephoning 1-800-927-4648.
Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Short Duration
PIMCO Low Duration Income
Short maturity fixed income instruments
0 to 3 years
Max 30% of total
assets below Baa(3)
No Limitation(4)
PIMCO Short Asset Investment
Money market instruments and short maturity
fixed income instruments
≤ 1.5 years
Baa to Aaa
0%
PIMCO Short-Term
Money market instruments and short maturity
fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below Baa
0-10% of total
assets(5)
PIMCO Low Duration
Short maturity fixed income instruments
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration II
Short maturity fixed income instruments with
quality and non-U.S. issuer restrictions
1 to 3 years
A to Aaa
0%
PIMCO Low Duration ESG
Short maturity fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
1 to 3 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Low Duration Credit(6)
Diversified portfolio of fixed income
instruments
0 to 3 years
Max 10% of total
assets below Caa
0-25% of total
assets(7)
Intermediate
Duration
PIMCO Moderate Duration
Short and intermediate maturity fixed income
instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO GNMA and Government
Securities
Short and intermediate maturity
mortgage-related fixed income securities issued
by the Government National Mortgage
Association and U.S. government securities
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa
0%
PIMCO High Yield
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(8) max
20% of total assets
Caa or below
0-20% of total
assets(5)
PIMCO High Yield Spectrum
High yielding fixed income securities
+/-1 year of its
benchmark
Min 80% of high yield
investments(9)
No Limitation(10)
PIMCO Mortgage-Backed Securities
Short and intermediate maturity
mortgage-related fixed income instruments
1 to 7 years
Baa to Aaa; max 10%
of total assets below
Aaa(11)
0%
PIMCO Total Return
Intermediate maturity fixed income instruments
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return II
Intermediate maturity fixed income instruments
with quality and non-U.S. issuer restrictions
+/-2 years of its
benchmark
Baa to Aaa
0%
PIMCO Total Return ESG
Intermediate maturity fixed income instruments
with prohibitions on firms engaged in socially
sensitive practices
+/-2 years of its
benchmark
Max 20% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Total Return IV
Intermediate maturity fixed income instruments
+/-1.5 years of its
benchmark
Baa to Aaa
0-15% of total
assets(7)
PIMCO Investment Grade Credit Bond
Investment grade fixed income securities
+/-2 years of its
benchmark
Max 15% of total
assets below Baa
0-30% of total
assets(5)

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Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
Long Duration
PIMCO Long Duration Total Return
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO Extended Duration
Long-term maturity fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO Long-Term U.S. Government
Long-term maturity fixed income securities
≥ 8 years
A to Aaa; max 25% Aa;
max 10% A
0%
PIMCO Mortgage Opportunities and
Bond
Mortgage-related assets and fixed income
instruments
(-1) to 8 years
Max 50% of total
assets below Baa(12)
0%
PIMCO Long-Term Credit Bond
Long-term maturity fixed income instruments
+/-2 years of its
benchmark
B to Aaa; max 20% of
total assets below Baa
0-30% of total
assets(5)
Income
PIMCO ESG Income
Broad range of fixed income instruments with
prohibitions on firms engaged in socially
sensitive practices
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Income
Broad range of fixed income instruments
0 to 8 years
Max 50% of total
assets below Baa(3)
No Limitation(4)
PIMCO Preferred and Capital Securities
Capital securities and preferred securities
+/-2 years of its
benchmark
No Limitation
No Limitation(4)
Inflation-Related
PIMCO Real Return
Inflation-indexed fixed income instruments
+/-3 years of its
benchmark
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO Long-Term Real Return
Inflation-indexed fixed income securities
+/-4 years of its
benchmark
B to Aaa; max 20% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO CommoditiesPLUS® Strategy
Commodity-linked derivative instruments
backed by an actively managed low volatility
portfolio of fixed income instruments
≤ 1 year
Max 10% of total
assets below Baa
0-20%(4)
PIMCO CommodityRealReturn Strategy®
Commodity-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
PIMCO RealEstateRealReturn Strategy
Real estate-linked derivative instruments
backed by a portfolio of inflation-indexed
securities and other fixed income instruments
≤ 10 years
Max 10% of total
assets below Baa
0-30% of total
assets(5)
Tax Exempt
PIMCO California Short Duration
Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal and California
income tax)
≤ 3 years
Caa to Aaa; max 10%
of total assets below
Baa
0%
PIMCO California Municipal Bond
Municipal securities (exempt from federal and
California income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO Short Duration Municipal Income
Short to intermediate maturity municipal
securities (exempt from federal income tax)
≤ 3 years
Baa to Aaa
0%
PIMCO California Intermediate Municipal
Bond
Intermediate maturity municipal securities
(exempt from federal and California income
tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO National Intermediate Municipal
Bond
Municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
Max 10% of total
assets below Baa
0%
PIMCO New York Municipal Bond
Intermediate to long-term maturity municipal
securities (exempt from federal and New York
income tax)
(-2) to 4 years of
its benchmark
Max 20% of total
assets below Baa
0%
PIMCO High Yield Municipal Bond
Intermediate to long-term maturity high yield
municipal securities (exempt from federal
income tax)
(-2) to 4 years of
its benchmark
No Limitation
0%

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PIMCO Variable Insurance Trust

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
PIMCO Emerging Markets Bond
Emerging market fixed income instruments
+/- 2 years of its
benchmark
Max 15% of total
assets below B
≥ 80% of assets(14)
PIMCO Emerging Markets Currency and
Short-Term Investments
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and short-term investments
≤ 2 years
Max 15% of total
assets below B
No Limitation(15)
PIMCO International Bond
(U.S. Dollar-Hedged)
Intermediate maturity hedged non-U.S. fixed
income instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO International Bond (Unhedged)
Intermediate maturity non-U.S. fixed income
instruments
+/-3 years of its
benchmark
Max 10% of total
assets below Baa
No Limitation
PIMCO Global Advantage® Strategy
Bond
U.S. and non-U.S. fixed income instruments
≤ 8 years
Max 15% of total
assets below B
No Limitation
PIMCO Global Bond Opportunities
(U.S. Dollar-Hedged)
U.S. and hedged non-U.S. intermediate maturity
fixed income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation(5)
PIMCO Global Bond Opportunities
(Unhedged)
U.S. and non-U.S. intermediate maturity fixed
income instruments
2 to 8 years
Max 10% of total
assets below Baa
No Limitation
PIMCO Diversified Income
Investment grade corporate, high yield and
emerging market fixed income instruments
3 to 8 years
Max 10% below B
No Limitation
PIMCO Emerging Markets Local Currency
and Bond
Currencies of, or fixed income instruments
denominated in currencies of, emerging market
countries and fixed income instruments
+/-2 years of its
benchmark
Max 15% of total
assets below B
No Limitation(16)
PIMCO Emerging Markets Corporate
Bond
Diversified portfolio of fixed income
instruments economically tied to emerging
market countries
+/- 2 years of its
benchmark
Max 15% of total
assets below B
No Limitation
Absolute Return
PIMCO Dynamic Bond
Diversified portfolio of fixed income
instruments
(-3) to 8 years
Max 40% of total
assets below Baa
No Limitation(17)
PIMCO Strategic Bond
Diversified portfolio of fixed income
instruments
(-1) to 5 years
Max 20% of total
assets below Baa
No Limitation(18)
PIMCO Credit Opportunities Bond
Diversified portfolio of fixed income
instruments
0 to 6 years
Max 50% of total
assets below B-
No Limitation(5)
PIMCO TRENDS Managed Futures
Strategy
Financial and commodity-linked derivative
instruments selected by a quantitative strategy
and generally backed by a short to intermediate
duration portfolio which may consist of cash
equivalent securities and fixed income
instruments
N/A
No Limitation
No Limitation
PIMCO RAE Fundamental Advantage
PLUS
Long exposure to RAE US Large Model
Portfolio, short exposure to the S&P 500 Index,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(17)
PIMCO Climate Bond
Diversified portfolio of fixed income
instruments
2 to 8 years
Max 25% of total
assets below Baa
No Limitation(5)
Domestic
Equity-Related
PIMCO RAE PLUS
Exposure to RAE US Large Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(17)
PIMCO StocksPLUS® Small
Russell 2000® Index derivatives backed by a
diversified portfolio of actively managed fixed
income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS® Long Duration
S&P 500 Index derivatives backed by a
diversified portfolio of long-term fixed income
instruments
+/-2 years of
Bloomberg
Barclays
Long-Term
Government/Credit
Index(20)
B to Aaa; max 10% of
total assets below Baa
0-30% of total
assets(5)
PIMCO StocksPLUS® Absolute Return
S&P 500 Index derivatives backed by a portfolio
of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(17)
PIMCO StocksPLUS®
S&P 500 Index derivatives backed by a portfolio
of short-term fixed income instruments
≤ 1 year
B to Aaa; max 10% of
total assets below
Baa(13)
0-30% of total
assets(5)
PIMCO RAE PLUS Small
Exposure to RAE US Small Model Portfolio
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(13)
PIMCO RAE US
Exposure to RAE US Portfolio
N/A
N/A
0%
PIMCO RAE US Small
Exposure to RAE US Small Portfolio
N/A
N/A
0%

48  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Category
Underlying PIMCO Fund
Main Investments
Duration
Credit Quality(1)
Non-U.S. Dollar
Denominated
Instruments(2)
International
Equity-Related
PIMCO Dividend and Income
Exposure to RAE Income Global Portfolio in
Equity Sleeve; remainder of portfolio invests in
fixed income instruments of varying maturities
N/A
No Limitation
No Limitation
PIMCO RAE PLUS EMG
Exposure to RAE Emerging Markets Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO StocksPLUS® International
(Unhedged)
Non-U.S. equity derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO StocksPLUS® International
(U.S. Dollar-Hedged)
Non-U.S. equity derivatives (hedged to
U.S. dollars) backed by a portfolio of fixed
income instruments.
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(19)
PIMCO RAE PLUS International
Exposure to RAE International Large Model
Portfolio complemented by a portfolio of fixed
income instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE Worldwide Long/Short PLUS
Long exposure to RAE Low Volatility U.S. Model
Portfolio, RAE Low Volatility Intl Model Portfolio
and RAE Low Volatility EMG Model Portfolio,
short exposure to certain traditional
capitalization-weighted equity indexes,
complemented by a portfolio of fixed income
instruments
(-3) to 8 years
Max 20% of total
assets below Baa
No Limitation(19)
PIMCO RAE Emerging Markets
Exposure to RAE Emerging Markets Portfolio
N/A
N/A
No Limitation
PIMCO RAE International
Exposure to RAE International Portfolio
N/A
N/A
No Limitation
U.S. Government
Securities
PIMCO Government Money Market
U.S. government securities
≤ 60 days
dollar-weighted
average maturity
Min 97% of total
assets Prime 1; ≤ 3%
of total assets Prime 2
0%
Short Strategy
PIMCO StocksPLUS® Short
Short S&P 500 Index derivatives backed by a
portfolio of fixed income instruments
(-3) to 8 years
B to Aaa; max 20% of
total assets below
Baa(13)
No Limitation(17)
1
As rated by Moody's, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality.
2
Certain Underlying PIMCO Funds may invest beyond these limits in U.S. dollar-denominated instruments of non-U.S. issuers.
3
Such limitation shall not apply to the Fund's investments in mortgage- and asset-backed securities.
4
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 10% of its total assets.
5
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
6
Effective May 3, 2021, the PIMCO Senior Floating Rate Fund changed its name to PIMCO Low Duration Credit Fund. Information for the PIMCO Low Duration Credit Fund is effective as of May 3, 2021.
7
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 5% of its total assets.
8
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index.
9
High yield investments include securities (i) rated below investment grade by each of Moody's, S&P or Fitch that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML Developed Markets High Yield Constrained (USD Hedged) Index.
10
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to within 10% (plus or minus) of the Fund's benchmark's foreign currency exposure.
11
The Fund may also invest up to an additional 5% of its total assets in mortgage-related high yield instruments rated below Baa.
12
Such limitation shall not apply to the Fund's investments in mortgage-related securities.
13
Within such limitation, the Fund may invest in mortgage-related securities rated below B.
14
The percentage limitation relates to Fixed Income Instruments of non-U.S. issuers denominated in any currency.
15
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or in Fixed Income Instruments denominated in the currencies of, emerging market countries, and in short-term investments.
16
The Fund seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in currencies of, or Fixed Income Instruments denominated in the currencies of, emerging market countries and in Fixed Income Instruments, each of which may be represented by forwards or derivatives such as options, futures contracts or swap agreements.
17
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
18
The Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 25% of its total assets.
19
With respect to the Fund's fixed income investments, the Fund will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 35% of its total assets.
20
The Bloomberg Barclays Long-Term Government/Credit Index is an unmanaged index of U.S. Government or investment grade credit securities having a maturity of 10 years or more.

April 30, 2021 | PROSPECTUS  49

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Global Managed Asset Allocation Portfolio
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$12.53
$0.13
$1.72
$1.85
$(0.99)
$(0.24)
$0.00
$(1.23)
12/31/2019
10.94
0.29
1.58
1.87
(0.28)
0.00
0.00
(0.28)
12/31/2018
12.83
0.31
(0.97)
(0.66)
(0.23)
(1.00)
0.00
(1.23)
12/31/2017
11.50
0.27
1.36
1.63
(0.30)
0.00
0.00
(0.30)
12/31/2016
11.33
0.26
0.21
0.47
0.00
0.00
(0.30)
(0.30)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratios shown do not include expenses of the investment companies in which the Portfolio may invest. See Note 9, Fees and Expenses, in the Notes to Financial Statements for more information regarding the expenses and any applicable fee waivers associated with these investments.

50  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets(d)
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$13.15
17.01%
$1,166
0.82%
1.02%
0.80%
1.00%
1.06%
360%
12.53
17.23
1,972
0.88
1.04
0.83
0.99
2.41
694
10.94
(5.32)
1,687
0.90
1.05
0.84
0.99
2.46
693
12.83
14.24
1,789
0.88
1.03
0.84
0.99
2.20
381
11.50
4.20
1,571
0.82
1.01
0.79
0.98
2.31
412

April 30, 2021 | PROSPECTUS  51

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2053F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
INTERMEDIATE DURATION BOND PORTFOLIO
PIMCO High Yield Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO High Yield Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.60%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.79%
1
“Other Expenses” include interest expense of 0.04%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.75% for Administrative Class shares.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$81
$252
$439
$978
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 31% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in high yield investments (“junk bonds”), which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. High yield investments include securities (i) rated below investment grade by each of Moody’s Investors Services, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”) that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index. The Portfolio may invest up to 20% of its total assets in securities rated Caa or below by Moody’s, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality. The remainder of the Portfolio’s assets may be invested in investment grade Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of this Portfolio normally varies within two years (plus or minus) of the portfolio duration of the securities comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index, as calculated by PIMCO, which as of February 28, 2021 was 3.89 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio may invest up to 20% of its total assets in securities denominated in foreign currencies and may invest without limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets. The Portfolio may invest up to 15% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 20% of its total assets in such instruments).
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may invest up to 10% of its total assets in preferred securities.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the
underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and

April 30, 2021 | PROSPECTUS  2

PIMCO High Yield Portfolio

the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index tracks the performance of BB-B rated U.S. Dollar-denominated corporate bonds publicly issued in the U.S. domestic market. Qualifying bonds are capitalization-weighted provided the total allocation to an individual issuer (defined by Bloomberg tickers) does not exceed 2%. Issuers that exceed the limit are reduced to 2% and the face value of each of their bonds is adjusted on a pro-rata basis. Similarly, the face value of bonds of all other issuers that fall below the 2% cap are increased on a pro-rata basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
June 30, 2020
8.37%
Worst Quarter
March 31, 2020
-11.24%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Administrative Class Return
5.75%
7.20%
6.04%
ICE BofAML U.S. High Yield, BB-B Rated, Constrained
Index (reflects no deductions for fees, expenses or taxes)
6.28%
8.02%
6.63%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Jessop and Sonali Pier. Mr. Jessop is a Managing Director of PIMCO and has managed the Portfolio since January 2010. Ms. Pier is a Managing Director of PIMCO and has managed the Portfolio since July 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

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Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of mispricing or improper valuation and the risk that changes in the value of the derivative instrument may not correlate perfectly with the underlying asset, rate or index. By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa.

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Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets

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in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.

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Prospectus

Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.60% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.35% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO High Yield
Andrew Jessop
1/10
Managing Director, PIMCO. Mr. Jessop joined PIMCO in 2009, as a senior portfolio manager
and head of the high yield team. Prior to joining PIMCO, he was a managing director,
portfolio manager and co-head of the high yield group at Goldman Sachs Asset
Management, where he spent twelve years.
PIMCO High Yield
Sonali Pier
7/19
Managing Director, PIMCO. Ms. Pier is a portfolio manager focusing on multisector credit
opportunities. Prior to joining PIMCO in 2013, she was a senior credit trader at J.P. Morgan,
trading cash, recovery and credit default swaps across various sectors. She has investment
experience since 2003 and holds an undergraduate degree in economics from Princeton
University.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”), an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

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Prospectus

conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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PIMCO Variable Insurance Trust

fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Prospectus

Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them

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or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the
Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;

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structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares.
U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary

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market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds
may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness

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of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same
underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate.

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For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be
less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”

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  Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a
portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including

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convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income
Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other

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collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the
security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future

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economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the
value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to

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withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives
strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.

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Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the
markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.

April 30, 2021 | PROSPECTUS  29

PIMCO Variable Insurance Trust

ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling
a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

30  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

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PIMCO Variable Insurance Trust

Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to
additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolio does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

32  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO High Yield Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$7.95
$0.36
$0.07
$0.43
$(0.37)
$0.00
$0.00
$(0.37)
12/31/2019
7.28
0.37
0.68
1.05
(0.38)
0.00
0.00
(0.38)
12/31/2018
7.87
0.38
(0.58)
(0.20)
(0.39)
0.00
0.00
(0.39)
12/31/2017
7.75
0.37
0.13
0.50
(0.38)
0.00
0.00
(0.38)
12/31/2016
7.26
0.38
0.50
0.88
(0.39)
0.00
0.00
(0.39)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratio of expenses to average net assets includes line of credit expenses.

33  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$8.01
5.75%
$764,646
0.79%(d)
0.79%(d)
0.75%
0.75%
4.65%
31%
7.95
14.72
895,701
0.78(d)
0.78(d)
0.75
0.75
4.83
30
7.28
(2.65)
847,818
0.78(d)
0.78(d)
0.75
0.75
4.96
17
7.87
6.61
1,016,642
0.76(d)
0.76(d)
0.75
0.75
4.64
25
7.75
12.45
1,049,825
0.76(d)
0.76(d)
0.75
0.75
5.09
30

April 30, 2021 | PROSPECTUS  34

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0337F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
INTERMEDIATE DURATION BOND PORTFOLIO
PIMCO High Yield Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO High Yield Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.60%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.89%
1
“Other Expenses” include interest expense of 0.04%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.85% for Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$91
$284
$493
$1,096
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 31% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in high yield investments (“junk bonds”), which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. High yield investments include securities (i) rated below investment grade by each of Moody’s Investors Services, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”) that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index. The Portfolio may invest up to 20% of its total assets in securities rated Caa or below by Moody’s, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality. The remainder of the Portfolio’s assets may be invested in investment grade Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of this Portfolio normally varies within two years (plus or minus) of the portfolio duration of the securities comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index, as calculated by PIMCO, which as of February 28, 2021 was 3.89 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio may invest up to 20% of its total assets in securities denominated in foreign currencies and may invest without limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets. The Portfolio may invest up to 15% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 20% of its total assets in such instruments).
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may invest up to 10% of its total assets in preferred securities.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the
underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and

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PIMCO High Yield Portfolio

the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index tracks the performance of BB-B rated U.S. Dollar-denominated corporate bonds publicly issued in the U.S. domestic market. Qualifying bonds are capitalization-weighted provided the total allocation to an individual issuer (defined by Bloomberg tickers) does not exceed 2%. Issuers that exceed the limit are reduced to 2% and the face value of each of their bonds is adjusted on a pro-rata basis. Similarly, the face value of bonds of all other issuers that fall below the 2% cap are increased on a pro-rata basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
June 30, 2020
8.35%
Worst Quarter
March 31, 2020
-11.26%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Advisor Class Return
5.64%
7.09%
5.93%
ICE BofAML U.S. High Yield, BB-B Rated, Constrained
Index (reflects no deductions for fees, expenses or taxes)
6.28%
8.02%
6.63%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Jessop and Sonali Pier. Mr. Jessop is a Managing Director of PIMCO and has managed the Portfolio since January 2010. Ms. Pier is a Managing Director of PIMCO and has managed the Portfolio since July 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of mispricing or improper valuation and the risk that changes in the value of the derivative instrument may not correlate perfectly with the underlying asset, rate or index. By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa.

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Prospectus

Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets

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PIMCO Variable Insurance Trust

in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.

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Prospectus

Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.60% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.35% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO High Yield
Andrew Jessop
1/10
Managing Director, PIMCO. Mr. Jessop joined PIMCO in 2009, as a senior portfolio manager
and head of the high yield team. Prior to joining PIMCO, he was a managing director,
portfolio manager and co-head of the high yield group at Goldman Sachs Asset
Management, where he spent twelve years.
PIMCO High Yield
Sonali Pier
7/19
Managing Director, PIMCO. Ms. Pier is a portfolio manager focusing on multisector credit
opportunities. Prior to joining PIMCO in 2013, she was a senior credit trader at J.P. Morgan,
trading cash, recovery and credit default swaps across various sectors. She has investment
experience since 2003 and holds an undergraduate degree in economics from Princeton
University.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

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circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;

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inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition,

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imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond
program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the

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volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools
because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.

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Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid
insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other

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asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or
losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy

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common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical

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service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.

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Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which
involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro

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cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates,
commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to

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the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited
to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.

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Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will
decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to

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$1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established
secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In

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such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in
achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or

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unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolio does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO High Yield Portfolio
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$7.95
$0.35
$0.07
$0.42
$(0.36)
$0.00
$0.00
$(0.36)
12/31/2019
7.28
0.37
0.68
1.05
(0.38)
0.00
0.00
(0.38)
12/31/2018
7.87
0.37
(0.58)
(0.21)
(0.38)
0.00
0.00
(0.38)
12/31/2017
7.75
0.36
0.14
0.50
(0.38)
0.00
0.00
(0.38)
12/31/2016
7.26
0.37
0.51
0.88
(0.39)
0.00
0.00
(0.39)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratio of expenses to average net assets includes line of credit expenses.

34  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$8.01
5.64%
$19,470
0.89%(d)
0.89%(d)
0.85%
0.85%
4.51%
31%
7.95
14.61
33,523
0.88(d)
0.88(d)
0.85
0.85
4.73
30
7.28
(2.75)
16,190
0.88(d)
0.88(d)
0.85
0.85
4.83
17
7.87
6.50
29,721
0.86(d)
0.86(d)
0.85
0.85
4.53
25
7.75
12.34
41,147
0.86(d)
0.86(d)
0.85
0.85
4.96
30

April 30, 2021 | PROSPECTUS  35

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1878F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
INTERMEDIATE DURATION BOND PORTFOLIO
PIMCO High Yield Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO High Yield Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.60%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.64%
1
“Other Expenses” include interest expense of 0.04%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.60% for Institutional Class shares.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$65
$205
$357
$798
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 31% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in high yield investments (“junk bonds”), which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. High yield investments include securities (i) rated below investment grade by each of Moody’s Investors Services, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”) that provides a rating on such investment or, if unrated, determined by PIMCO to be of comparable quality, or (ii) comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index. The Portfolio may invest up to 20% of its total assets in securities rated Caa or below by Moody’s, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality. The remainder of the Portfolio’s assets may be invested in investment grade Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of this Portfolio normally varies within two years (plus or minus) of the portfolio duration of the securities comprising the ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index, as calculated by PIMCO, which as of February 28, 2021 was 3.89 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio may invest up to 20% of its total assets in securities denominated in foreign currencies and may invest without limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets. The Portfolio may invest up to 15% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 20% of its total assets in such instruments).
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may invest up to 10% of its total assets in preferred securities.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the
underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and

April 30, 2021 | PROSPECTUS  2

PIMCO High Yield Portfolio

the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The ICE BofAML U.S. High Yield, BB-B Rated, Constrained Index tracks the performance of BB-B rated U.S. Dollar-denominated corporate bonds publicly issued in the U.S. domestic market. Qualifying bonds are capitalization-weighted provided the total allocation to an individual issuer (defined by Bloomberg tickers) does not exceed 2%. Issuers that exceed the limit are reduced to 2% and the face value of each of their bonds is adjusted on a pro-rata basis. Similarly, the face value of bonds of all other issuers that fall below the 2% cap are increased on a pro-rata basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class
Best Quarter
June 30, 2020
8.41%
Worst Quarter
March 31, 2020
-11.21%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Institutional Class Return
5.90%
7.36%
6.19%
ICE BofAML U.S. High Yield, BB-B Rated, Constrained
Index (reflects no deductions for fees, expenses or taxes)
6.28%
8.02%
6.63%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Jessop and Sonali Pier. Mr. Jessop is a Managing Director of PIMCO and has managed the Portfolio since January 2010. Ms. Pier is a Managing Director of PIMCO and has managed the Portfolio since July 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of mispricing or improper valuation and the risk that changes in the value of the derivative instrument may not correlate perfectly with the underlying asset, rate or index. By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa.

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Prospectus

Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.
Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets

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in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.
Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.60% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.35% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

12  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO High Yield
Andrew Jessop
1/10
Managing Director, PIMCO. Mr. Jessop joined PIMCO in 2009, as a senior portfolio manager
and head of the high yield team. Prior to joining PIMCO, he was a managing director,
portfolio manager and co-head of the high yield group at Goldman Sachs Asset
Management, where he spent twelve years.
PIMCO High Yield
Sonali Pier
7/19
Managing Director, PIMCO. Ms. Pier is a portfolio manager focusing on multisector credit
opportunities. Prior to joining PIMCO in 2013, she was a senior credit trader at J.P. Morgan,
trading cash, recovery and credit default swaps across various sectors. She has investment
experience since 2003 and holds an undergraduate degree in economics from Princeton
University.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

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From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

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investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder

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purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.

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Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by

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the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may
participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying

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property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real
estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and

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equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign
governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.

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Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.

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Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political
subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes

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in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which
they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or

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otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant
foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but

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only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in
“Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are

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relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies
involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.

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Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled
vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no

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added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a
portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not

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PIMCO Variable Insurance Trust

evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents,
custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolio does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

32  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO High Yield Portfolio
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$7.95
$0.37
$0.07
$0.44
$(0.38)
$0.00
$0.00
$(0.38)
12/31/2019
7.28
0.39
0.68
1.07
(0.40)
0.00
0.00
(0.40)
12/31/2018
7.87
0.39
(0.58)
(0.19)
(0.40)
0.00
0.00
(0.40)
12/31/2017
7.75
0.38
0.14
0.52
(0.40)
0.00
0.00
(0.40)
12/31/2016
7.26
0.40
0.49
0.89
(0.40)
0.00
0.00
(0.40)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.
(d)
Ratio of expenses to average net assets includes line of credit expenses.

33  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets(d)
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$8.01
5.90%
$10,147
0.64%(d)
0.64%(d)
0.60%
0.60%
4.79%
31%
7.95
14.90
11,169
0.63(d)
0.63(d)
0.60
0.60
4.97
30
7.28
(2.50)
9,211
0.63(d)
0.63(d)
0.60
0.60
5.11
17
7.87
6.77
10,863
0.61(d)
0.61(d)
0.60
0.60
4.80
25
7.75
12.61
9,937
0.61(d)
0.61(d)
0.60
0.60
5.24
30

April 30, 2021 | PROSPECTUS  34

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0548S_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
INTERMEDIATE DURATION BOND PORTFOLIO
PIMCO Income Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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1
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36
A-1


PIMCO Income Portfolio

Investment Objective
The Portfolio’s primary investment objective is to maximize current income. Long-term capital appreciation is a secondary objective.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.65%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.84%
1
“Other Expenses” include interest expense of 0.03%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.81% for Administrative Class shares.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$86
$268
$466
$1,037
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 390% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objectives by investing under normal circumstances at least 65% of its total assets in a multi-sector portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio will seek to maintain a high and consistent level of dividend income by investing in a broad array of fixed income sectors and utilizing strategies that seek to optimize portfolio income (i.e., strategies that prioritize current income over total return). The capital appreciation sought by the Portfolio generally arises from decreases in interest rates or improving credit fundamentals for a particular sector or security.
The Portfolio will generally allocate its assets among several investment sectors, without limitation, which may include: (i) high yield securities (“junk bonds”) and investment grade corporate bonds of issuers located in the United States and non-U.S. countries, including emerging market countries; (ii) fixed income securities issued by U.S. and non-U.S. governments (including emerging market governments), their agencies and instrumentalities; (iii) mortgage-related and other asset backed securities; and (iv) foreign currencies, including those of emerging market countries. However, the Portfolio is not required to gain exposure to any one investment sector, and the Portfolio’s exposure to any one investment sector will vary over time. The average portfolio duration of this Portfolio normally varies from zero to eight years based on PIMCO’s forecast for interest rates. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio may invest up to 50% of its total assets in high yield securities rated below investment grade by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or if unrated, as determined by PIMCO (except such 50% limitation shall not apply to the Portfolio’s investments in mortgage- and asset-backed securities). In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. In addition, the Portfolio may invest, without limitation, in securities denominated in foreign currencies and in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 20% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest in such instruments without limitation subject to any applicable legal or regulatory limitation). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 10% of its total assets.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buybacks or dollar rolls). The Portfolio may also invest in contingent convertible securities and up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and
may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s

April 30, 2021 | PROSPECTUS  2

PIMCO Income Portfolio

inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Distribution Rate Risk:the risk that the Portfolio’s distribution rate may change unexpectedly as a result of numerous factors, including changes in realized and projected market returns, fluctuations in market interest rates, Portfolio performance and other factors
Contingent Convertible Securities Risk:the risks of investing in contingent convertible securities, including the risk that interest payments will be cancelled by the issuer or a regulatory authority, the risk of ranking junior to other creditors in the event of a liquidation or other bankruptcy-related event as a result of holding subordinated debt, the risk of the Portfolio’s investment becoming further subordinated as a result of conversion from debt to equity, the risk that principal amount due can be written down to a lesser amount, and the general risks applicable to fixed income investments, including interest rate risk, credit risk, market risk and liquidity risk, any of which could result in losses to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable, and dollar denominated. The index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
June 30, 2020
7.81%
Worst Quarter
March 31, 2020
-7.90%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
Since
Inception
Inception
Date
Administrative Class Return
6.51%
6.25%
4/29/2016
Bloomberg Barclays U.S. Aggregate Index (reflects
no deductions for fees, expenses or taxes)
7.51%
4.00%
 

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Daniel J. Ivascyn, Alfred Murata and Joshua Anderson. Mr. Ivascyn is Group Chief Investment Officer and a Managing Director of PIMCO. Messrs. Murata and Anderson are Managing Directors of PIMCO. Messrs. Ivascyn and Murata have managed the Portfolio since its inception in April 2016. Mr. Anderson has managed the Portfolio since July 2018.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk to the extent it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Distribution Rate Risk
Although the Portfolio may seek to maintain a level distribution rate, the Portfolio’s distribution rate may be affected by numerous factors, including but not limited to changes in realized and projected market returns, fluctuations in market interest rates, Portfolio performance, and other factors. For instance, during periods of low or declining interest rates, the Portfolio’s distributable income and dividend levels may decline for many reasons. There can be no assurance that a change in market conditions or other factors will not result in a change in the Portfolio’s distribution rate or that the rate will be sustainable in the future.
Contingent Convertible Securities Risk
Contingent convertible securities (“CoCos”) have no stated maturity, have fully discretionary coupons and are typically issued in the form of subordinated debt instruments. CoCos generally either convert into equity or have their principal written down upon the occurrence of certain triggering events (“triggers”) linked to regulatory capital thresholds or regulatory actions relating to the issuer’s continued viability. As a result, an investment by the Portfolio in CoCos is subject to the risk that coupon (i.e., interest) payments may be cancelled by the issuer or a regulatory authority in order to help the issuer absorb losses. An investment by the Portfolio in CoCos is also subject to the risk that, in the event of the liquidation, dissolution or winding-up of an issuer prior to a trigger event, the Portfolio’s rights and claims will generally rank junior to the claims of holders of the issuer’s other debt obligations. In addition, if CoCos held by the Portfolio are converted into the issuer’s underlying equity securities following a trigger event, the Portfolio’s holding may be further subordinated due to the conversion from a debt to equity instrument. Further, the value of an investment in CoCos is unpredictable and will be influenced by many factors and risks, including interest rate risk, credit risk, market risk and liquidity risk. An investment by the Portfolio in CoCos may result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.65% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.40% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager
Since
Recent Professional Experience
PIMCO Income
Joshua Anderson
7/18
Managing Director, PIMCO. Mr. Anderson is a portfolio manager focusing on global structured
credit investments. Prior to joining PIMCO in 2003, he was an analyst at Merrill Lynch covering
both the residential ABS and collateralized debt obligation sectors and was ranked as one of
the top analysts by Institutional Investor magazine. He was previously a portfolio manager at
Merrill Lynch Investment Managers.
PIMCO Income
Daniel J. Ivascyn
4/16*
Group Chief Investment Officer and Managing Director, PIMCO. Mr. Ivascyn joined PIMCO in
1998, previously having been associated with Bear Stearns in the asset backed securities
group, as well as T. Rowe Price and Fidelity Investments. He has investment experience since
1992 and holds an MBA in analytic finance from the University of Chicago Graduate School of
Business and a bachelor's degree in economics from Occidental College.
PIMCO Income
Alfred Murata
4/16*
Managing Director, PIMCO. Mr. Murata is a portfolio manager on the mortgage credit team.
Prior to joining PIMCO in 2001, he researched and implemented exotic equity and interest
rate derivatives at Nikko Financial Technologies.
*
Inception of the Portfolio.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”), an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

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Prospectus

conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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PIMCO Variable Insurance Trust

fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Prospectus

Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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PIMCO Variable Insurance Trust

Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them

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or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the
Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;

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repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported
by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing

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out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond
the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of

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the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower
characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the

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current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that
are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a

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smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable

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generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.
The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined

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by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,
PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for

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many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign
currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.

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Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with

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many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or
holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive

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most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules
and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good
faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Portfolio Distribution Rates
Although the Portfolio may seek to maintain level distributions, distribution rates may be affected by numerous factors, including but not limited to changes in realized and projected market returns, fluctuations in market interest rates, Portfolio performance, and other factors. There can be no assurance that a change in market conditions or other factors will not result in a change in the Portfolio’s distribution rate or that the rate will be sustainable in the future.
For instance, during periods of low or declining interest rates, the Portfolio’s distributable income and dividend levels may decline for many reasons. For example, the Portfolio may have to deploy uninvested assets (whether from purchases of Portfolio shares, proceeds from matured, traded or called debt obligations or other sources) in new, lower yielding instruments. Additionally, payments from certain instruments that may be held by the Portfolio (such as variable and floating rate securities) may be negatively impacted by declining interest rates, which may also lead to a decline in the Portfolio’s distributable income and dividend levels.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income

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PIMCO Variable Insurance Trust

instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio managers' creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt

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normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Income Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$10.87
$0.36
$0.31
$0.67
$(0.50)
$(0.03)
$0.00
$(0.53)
12/31/2019
10.37
0.43
0.45
0.88
(0.38)
0.00
0.00
(0.38)
12/31/2018
10.74
0.40
(0.37)
0.03
(0.33)
(0.07)
0.00
(0.40)
12/31/2017
10.19
0.35
0.47
0.82
(0.27)
0.00
0.00
(0.27)
04/29/2016 - 12/31/2016
10.00
0.22
0.36
0.58
(0.37)
(0.02)
0.00
(0.39)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
*
Annualized
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.01
6.51%
$159,538
0.84%
0.84%
0.81%
0.81%
3.40%
390%
10.87
8.57
141,089
0.97
0.97
0.80
0.80
4.00
267
10.37
0.39
96,244
1.04
1.04
0.80
0.80
3.83
188
10.74
8.08
85,702
0.82
0.82
0.80
0.80
3.27
206
10.19
5.82
17,864
0.80 *
0.84 *
0.80 *
0.84 *
3.19 *
203

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

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PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2164F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
INTERMEDIATE DURATION BOND PORTFOLIO
PIMCO Income Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Income Portfolio

Investment Objective
The Portfolio’s primary investment objective is to maximize current income. Long-term capital appreciation is a secondary objective.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.65%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.94%
1
“Other Expenses” include interest expense of 0.03%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.91% for Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$96
$300
$520
$1,155
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 390% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objectives by investing under normal circumstances at least 65% of its total assets in a multi-sector portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio will seek to maintain a high and consistent level of dividend income by investing in a broad array of fixed income sectors and utilizing strategies that seek to optimize portfolio income (i.e., strategies that prioritize current income over total return). The capital appreciation sought by the Portfolio generally arises from decreases in interest rates or improving credit fundamentals for a particular sector or security.
The Portfolio will generally allocate its assets among several investment sectors, without limitation, which may include: (i) high yield securities (“junk bonds”) and investment grade corporate bonds of issuers located in the United States and non-U.S. countries, including emerging market countries; (ii) fixed income securities issued by U.S. and non-U.S. governments (including emerging market governments), their agencies and instrumentalities; (iii) mortgage-related and other asset backed securities; and (iv) foreign currencies, including those of emerging market countries. However, the Portfolio is not required to gain exposure to any one investment sector, and the Portfolio’s exposure to any one investment sector will vary over time. The average portfolio duration of this Portfolio normally varies from zero to eight years based on PIMCO’s forecast for interest rates. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio may invest up to 50% of its total assets in high yield securities rated below investment grade by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or if unrated, as determined by PIMCO (except such 50% limitation shall not apply to the Portfolio’s investments in mortgage- and asset-backed securities). In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. In addition, the Portfolio may invest, without limitation, in securities denominated in foreign currencies and in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 20% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest in such instruments without limitation subject to any applicable legal or regulatory limitation). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 10% of its total assets.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buybacks or dollar rolls). The Portfolio may also invest in contingent convertible securities and up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and
may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s

April 30, 2021 | PROSPECTUS  2

PIMCO Income Portfolio

inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Distribution Rate Risk:the risk that the Portfolio’s distribution rate may change unexpectedly as a result of numerous factors, including changes in realized and projected market returns, fluctuations in market interest rates, Portfolio performance and other factors
Contingent Convertible Securities Risk:the risks of investing in contingent convertible securities, including the risk that interest payments will be cancelled by the issuer or a regulatory authority, the risk of ranking junior to other creditors in the event of a liquidation or other bankruptcy-related event as a result of holding subordinated debt, the risk of the Portfolio’s investment becoming further subordinated as a result of conversion from debt to equity, the risk that principal amount due can be written down to a lesser amount, and the general risks applicable to fixed income investments, including interest rate risk, credit risk, market risk and liquidity risk, any of which could result in losses to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable, and dollar denominated. The index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
June 30, 2020
7.79%
Worst Quarter
March 31, 2020
-7.92%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
Since
Inception
Inception
Date
Advisor Class Return
6.41%
6.14%
4/29/2016
Bloomberg Barclays U.S. Aggregate Index (reflects
no deductions for fees, expenses or taxes)
7.51%
4.00%
 

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Daniel J. Ivascyn, Alfred Murata and Joshua Anderson. Mr. Ivascyn is Group Chief Investment Officer and a Managing Director of PIMCO. Messrs. Murata and Anderson are Managing Directors of PIMCO. Messrs. Ivascyn and Murata have managed the Portfolio since its inception in April 2016. Mr. Anderson has managed the Portfolio since July 2018.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk to the extent it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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PIMCO Variable Insurance Trust

transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Distribution Rate Risk
Although the Portfolio may seek to maintain a level distribution rate, the Portfolio’s distribution rate may be affected by numerous factors, including but not limited to changes in realized and projected market returns, fluctuations in market interest rates, Portfolio performance, and other factors. For instance, during periods of low or declining interest rates, the Portfolio’s distributable income and dividend levels may decline for many reasons. There can be no assurance that a change in market conditions or other factors will not result in a change in the Portfolio’s distribution rate or that the rate will be sustainable in the future.
Contingent Convertible Securities Risk
Contingent convertible securities (“CoCos”) have no stated maturity, have fully discretionary coupons and are typically issued in the form of subordinated debt instruments. CoCos generally either convert into equity or have their principal written down upon the occurrence of certain triggering events (“triggers”) linked to regulatory capital thresholds or regulatory actions relating to the issuer’s continued viability. As a result, an investment by the Portfolio in CoCos is subject to the risk that coupon (i.e., interest) payments may be cancelled by the issuer or a regulatory authority in order to help the issuer absorb losses. An investment by the Portfolio in CoCos is also subject to the risk that, in the event of the liquidation, dissolution or winding-up of an issuer prior to a trigger event, the Portfolio’s rights and claims will generally rank junior to the claims of holders of the issuer’s other debt obligations. In addition, if CoCos held by the Portfolio are converted into the issuer’s underlying equity securities following a trigger event, the Portfolio’s holding may be further subordinated due to the conversion from a debt to equity instrument. Further, the value of an investment in CoCos is unpredictable and will be influenced by many factors and risks, including interest rate risk, credit risk, market risk and liquidity risk. An investment by the Portfolio in CoCos may result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.65% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.40% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager
Since
Recent Professional Experience
PIMCO Income
Joshua Anderson
7/18
Managing Director, PIMCO. Mr. Anderson is a portfolio manager focusing on global structured
credit investments. Prior to joining PIMCO in 2003, he was an analyst at Merrill Lynch covering
both the residential ABS and collateralized debt obligation sectors and was ranked as one of
the top analysts by Institutional Investor magazine. He was previously a portfolio manager at
Merrill Lynch Investment Managers.
PIMCO Income
Daniel J. Ivascyn
4/16*
Group Chief Investment Officer and Managing Director, PIMCO. Mr. Ivascyn joined PIMCO in
1998, previously having been associated with Bear Stearns in the asset backed securities
group, as well as T. Rowe Price and Fidelity Investments. He has investment experience since
1992 and holds an MBA in analytic finance from the University of Chicago Graduate School of
Business and a bachelor's degree in economics from Occidental College.
PIMCO Income
Alfred Murata
4/16*
Managing Director, PIMCO. Mr. Murata is a portfolio manager on the mortgage credit team.
Prior to joining PIMCO in 2001, he researched and implemented exotic equity and interest
rate derivatives at Nikko Financial Technologies.
*
Inception of the Portfolio.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

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circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;

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bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of
the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be

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adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease
significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an

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obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored
mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the

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current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that
are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a

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smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable

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generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.
The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined

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by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,
PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for

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many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign
currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.

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Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with

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Prospectus

many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or
holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive

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most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules
and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good
faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Portfolio Distribution Rates
Although the Portfolio may seek to maintain level distributions, distribution rates may be affected by numerous factors, including but not limited to changes in realized and projected market returns, fluctuations in market interest rates, Portfolio performance, and other factors. There can be no assurance that a change in market conditions or other factors will not result in a change in the Portfolio’s distribution rate or that the rate will be sustainable in the future.
For instance, during periods of low or declining interest rates, the Portfolio’s distributable income and dividend levels may decline for many reasons. For example, the Portfolio may have to deploy uninvested assets (whether from purchases of Portfolio shares, proceeds from matured, traded or called debt obligations or other sources) in new, lower yielding instruments. Additionally, payments from certain instruments that may be held by the Portfolio (such as variable and floating rate securities) may be negatively impacted by declining interest rates, which may also lead to a decline in the Portfolio’s distributable income and dividend levels.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income

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PIMCO Variable Insurance Trust

instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio managers' creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt

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normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Income Portfolio
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$10.87
$0.35
$0.31
$0.66
$(0.49)
$(0.03)
$0.00
$(0.52)
12/31/2019
10.37
0.42
0.45
0.87
(0.37)
0.00
0.00
(0.37)
12/31/2018
10.74
0.39
(0.37)
0.02
(0.32)
(0.07)
0.00
(0.39)
12/31/2017
10.19
0.33
0.48
0.81
(0.26)
0.00
0.00
(0.26)
04/29/2016 - 12/31/2016
10.00
0.20
0.37
0.57
(0.36)
(0.02)
0.00
(0.38)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
*
Annualized
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

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Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.01
6.41%
$217,730
0.94%
0.94%
0.91%
0.91%
3.30%
390%
10.87
8.46
207,647
1.07
1.07
0.90
0.90
3.89
267
10.37
0.29
181,869
1.14
1.14
0.90
0.90
3.73
188
10.74
7.97
170,758
0.92
0.92
0.90
0.90
3.13
206
10.19
5.74
168,696
0.90 *
0.94 *
0.90 *
0.94 *
2.92 *
203

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

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PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

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Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

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PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

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PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2166F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
INTERMEDIATE DURATION BOND PORTFOLIO
PIMCO Income Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
Page
1
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5
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36
A-1


PIMCO Income Portfolio

Investment Objective
The Portfolio’s primary investment objective is to maximize current income. Long-term capital appreciation is a secondary objective.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.65%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.69%
1
“Other Expenses” include interest expense of 0.03%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.66% for Institutional Class shares.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$70
$221
$384
$859
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 390% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objectives by investing under normal circumstances at least 65% of its total assets in a multi-sector portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio will seek to maintain a high and consistent level of dividend income by investing in a broad array of fixed income sectors and utilizing strategies that seek to optimize portfolio income (i.e., strategies that prioritize current income over total return). The capital appreciation sought by the Portfolio generally arises from decreases in interest rates or improving credit fundamentals for a particular sector or security.
The Portfolio will generally allocate its assets among several investment sectors, without limitation, which may include: (i) high yield securities (“junk bonds”) and investment grade corporate bonds of issuers located in the United States and non-U.S. countries, including emerging market countries; (ii) fixed income securities issued by U.S. and non-U.S. governments (including emerging market governments), their agencies and instrumentalities; (iii) mortgage-related and other asset backed securities; and (iv) foreign currencies, including those of emerging market countries. However, the Portfolio is not required to gain exposure to any one investment sector, and the Portfolio’s exposure to any one investment sector will vary over time. The average portfolio duration of this Portfolio normally varies from zero to eight years based on PIMCO’s forecast for interest rates. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio may invest up to 50% of its total assets in high yield securities rated below investment grade by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or if unrated, as determined by PIMCO (except such 50% limitation shall not apply to the Portfolio’s investments in mortgage- and asset-backed securities). In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. In addition, the Portfolio may invest, without limitation, in securities denominated in foreign currencies and in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 20% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest in such instruments without limitation subject to any applicable legal or regulatory limitation). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 10% of its total assets.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buybacks or dollar rolls). The Portfolio may also invest in contingent convertible securities and up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and
may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s

April 30, 2021 | PROSPECTUS  2

PIMCO Income Portfolio

inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Distribution Rate Risk:the risk that the Portfolio’s distribution rate may change unexpectedly as a result of numerous factors, including changes in realized and projected market returns, fluctuations in market interest rates, Portfolio performance and other factors
Contingent Convertible Securities Risk:the risks of investing in contingent convertible securities, including the risk that interest payments will be cancelled by the issuer or a regulatory authority, the risk of ranking junior to other creditors in the event of a liquidation or other bankruptcy-related event as a result of holding subordinated debt, the risk of the Portfolio’s investment becoming further subordinated as a result of conversion from debt to equity, the risk that principal amount due can be written down to a lesser amount, and the general risks applicable to fixed income investments, including interest rate risk, credit risk, market risk and liquidity risk, any of which could result in losses to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable, and dollar denominated. The index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class
Best Quarter
June 30, 2020
7.85%
Worst Quarter
March 31, 2020
-7.86%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
Since
Inception
Inception
Date
Institutional Class Return
6.67%
6.41%
4/29/2016
Bloomberg Barclays U.S. Aggregate Index (reflects
no deductions for fees, expenses or taxes)
7.51%
4.00%
 

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Daniel J. Ivascyn, Alfred Murata and Joshua Anderson. Mr. Ivascyn is Group Chief Investment Officer and a Managing Director of PIMCO. Messrs. Murata and Anderson are Managing Directors of PIMCO. Messrs. Ivascyn and Murata have managed the Portfolio since its inception in April 2016. Mr. Anderson has managed the Portfolio since July 2018.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk to the extent it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Distribution Rate Risk
Although the Portfolio may seek to maintain a level distribution rate, the Portfolio’s distribution rate may be affected by numerous factors, including but not limited to changes in realized and projected market returns, fluctuations in market interest rates, Portfolio performance, and other factors. For instance, during periods of low or declining interest rates, the Portfolio’s distributable income and dividend levels may decline for many reasons. There can be no assurance that a change in market conditions or other factors will not result in a change in the Portfolio’s distribution rate or that the rate will be sustainable in the future.
Contingent Convertible Securities Risk
Contingent convertible securities (“CoCos”) have no stated maturity, have fully discretionary coupons and are typically issued in the form of subordinated debt instruments. CoCos generally either convert into equity or have their principal written down upon the occurrence of certain triggering events (“triggers”) linked to regulatory capital thresholds or regulatory actions relating to the issuer’s continued viability. As a result, an investment by the Portfolio in CoCos is subject to the risk that coupon (i.e., interest) payments may be cancelled by the issuer or a regulatory authority in order to help the issuer absorb losses. An investment by the Portfolio in CoCos is also subject to the risk that, in the event of the liquidation, dissolution or winding-up of an issuer prior to a trigger event, the Portfolio’s rights and claims will generally rank junior to the claims of holders of the issuer’s other debt obligations. In addition, if CoCos held by the Portfolio are converted into the issuer’s underlying equity securities following a trigger event, the Portfolio’s holding may be further subordinated due to the conversion from a debt to equity instrument. Further, the value of an investment in CoCos is unpredictable and will be influenced by many factors and risks, including interest rate risk, credit risk, market risk and liquidity risk. An investment by the Portfolio in CoCos may result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.65% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.40% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager
Since
Recent Professional Experience
PIMCO Income
Joshua Anderson
7/18
Managing Director, PIMCO. Mr. Anderson is a portfolio manager focusing on global structured
credit investments. Prior to joining PIMCO in 2003, he was an analyst at Merrill Lynch covering
both the residential ABS and collateralized debt obligation sectors and was ranked as one of
the top analysts by Institutional Investor magazine. He was previously a portfolio manager at
Merrill Lynch Investment Managers.
PIMCO Income
Daniel J. Ivascyn
4/16*
Group Chief Investment Officer and Managing Director, PIMCO. Mr. Ivascyn joined PIMCO in
1998, previously having been associated with Bear Stearns in the asset backed securities
group, as well as T. Rowe Price and Fidelity Investments. He has investment experience since
1992 and holds an MBA in analytic finance from the University of Chicago Graduate School of
Business and a bachelor's degree in economics from Occidental College.
PIMCO Income
Alfred Murata
4/16*
Managing Director, PIMCO. Mr. Murata is a portfolio manager on the mortgage credit team.
Prior to joining PIMCO in 2001, he researched and implemented exotic equity and interest
rate derivatives at Nikko Financial Technologies.
*
Inception of the Portfolio.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

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From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

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investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder

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purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.

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PIMCO Variable Insurance Trust

Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal
Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is

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funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity
absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.

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One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore,

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the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds,

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the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and
equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.

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Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts
(“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product,

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rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the
“country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment

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opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of
another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some

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purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative

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instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or
price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.

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Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will
decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to

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$1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established
secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Portfolio Distribution Rates
Although the Portfolio may seek to maintain level distributions, distribution rates may be affected by numerous factors, including but not limited to changes in realized and projected market returns, fluctuations in market interest rates, Portfolio performance, and other factors. There can be no assurance that a change in market conditions or other factors will not result in a change in the Portfolio’s distribution rate or that the rate will be sustainable in the future.
For instance, during periods of low or declining interest rates, the Portfolio’s distributable income and dividend levels may decline for many reasons. For example, the Portfolio may have to deploy uninvested assets (whether from purchases of Portfolio shares, proceeds from matured, traded or called debt obligations or other sources) in new, lower yielding instruments. Additionally, payments from certain instruments that may be held by the Portfolio (such as variable and floating rate securities) may be negatively impacted by declining interest rates, which may also lead to a decline in the Portfolio’s distributable income and dividend levels.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in

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realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a
security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio managers' creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with

34  Prospectus | PIMCO Variable Insurance Trust

Prospectus

shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

April 30, 2021 | PROSPECTUS  35

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Income Portfolio
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$10.87
$0.38
$0.30
$0.68
$(0.51)
$(0.03)
$0.00
$(0.54)
12/31/2019
10.37
0.44
0.45
0.89
(0.39)
0.00
0.00
(0.39)
12/31/2018
10.74
0.45
(0.40)
0.05
(0.35)
(0.07)
0.00
(0.42)
12/31/2017
10.19
0.36
0.47
0.83
(0.28)
0.00
0.00
(0.28)
04/29/2016 - 12/31/2016
10.00
0.18
0.41
0.59
(0.38)
(0.02)
0.00
(0.40)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
*
Annualized
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.01
6.67%
$4,454
0.69%
0.69%
0.66%
0.66%
3.59%
390%
10.87
8.73
1,503
0.82
0.82
0.65
0.65
4.14
267
10.37
0.54
1,382
0.89
0.89
0.65
0.65
4.29
188
10.74
8.24
29
0.67
0.67
0.65
0.65
3.38
206
10.19
5.92
26
0.65 *
0.69 *
0.65 *
0.69 *
2.69 *
203

April 30, 2021 | PROSPECTUS  37

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2165S_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Class M
INTERMEDIATE DURATION BOND PORTFOLIO
PIMCO Income Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Income Portfolio

Investment Objective
The Portfolio’s primary investment objective is to maximize current income. Long-term capital appreciation is a secondary objective.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Class M shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Class M
Management Fees
0.65%
Distribution and/or Service (12b-1) Fees
0.45%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
1.14%
1
“Other Expenses” include interest expense of 0.03%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 1.11% for Class M shares.
Example.The Example is intended to help you compare the cost of investing in Class M shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Class M
$116
$362
$628
$1,386
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 390% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objectives by investing under normal circumstances at least 65% of its total assets in a multi-sector portfolio of Fixed Income Instruments of varying maturities,
which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio will seek to maintain a high and consistent level of dividend income by investing in a broad array of fixed income sectors and utilizing strategies that seek to optimize portfolio income (i.e., strategies that prioritize current income over total return). The capital appreciation sought by the Portfolio generally arises from decreases in interest rates or improving credit fundamentals for a particular sector or security.
The Portfolio will generally allocate its assets among several investment sectors, without limitation, which may include: (i) high yield securities (“junk bonds”) and investment grade corporate bonds of issuers located in the United States and non-U.S. countries, including emerging market countries; (ii) fixed income securities issued by U.S. and non-U.S. governments (including emerging market governments), their agencies and instrumentalities; (iii) mortgage-related and other asset backed securities; and (iv) foreign currencies, including those of emerging market countries. However, the Portfolio is not required to gain exposure to any one investment sector, and the Portfolio’s exposure to any one investment sector will vary over time. The average portfolio duration of this Portfolio normally varies from zero to eight years based on PIMCO’s forecast for interest rates. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio may invest up to 50% of its total assets in high yield securities rated below investment grade by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or if unrated, as determined by PIMCO (except such 50% limitation shall not apply to the Portfolio’s investments in mortgage- and asset-backed securities). In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. In addition, the Portfolio may invest, without limitation, in securities denominated in foreign currencies and in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 20% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest in such instruments without limitation subject to any applicable legal or regulatory limitation). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 10% of its total assets.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buybacks or dollar rolls). The Portfolio may also invest in contingent convertible securities and up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments

April 30, 2021 | PROSPECTUS  2

PIMCO Income Portfolio

in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Distribution Rate Risk:the risk that the Portfolio’s distribution rate may change unexpectedly as a result of numerous factors, including changes in realized and projected market returns, fluctuations in market interest rates, Portfolio performance and other factors
Contingent Convertible Securities Risk:the risks of investing in contingent convertible securities, including the risk that interest payments will be cancelled by the issuer or a regulatory authority, the risk of ranking junior to other creditors in the event of a liquidation or other bankruptcy-related event as a result of holding subordinated debt, the risk of the Portfolio’s investment becoming further subordinated as a result of conversion from debt to equity, the risk that principal amount due can be written down to a lesser amount, and the general risks applicable to fixed income investments, including interest rate risk, credit risk, market risk and liquidity risk, any of which could result in losses to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s
performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable, and dollar denominated. The index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class (1)
Best Quarter
June 30, 2020
7.81%
Worst Quarter
March 31, 2020
-7.90%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
Since
Inception
Inception
Date
Administrative Class Return
6.51%
6.25%
4/29/2016
Bloomberg Barclays U.S. Aggregate Index (reflects
no deductions for fees, expenses or taxes)
7.51%
4.00%
 
(1)
Since the Portfolio’s Class M has not commenced operations as of the date of this prospectus, the bar chart and the table show performance of the Portfolio’s Administrative Class shares, which are offered in a separate prospectus. Although Class M and Administrative Class would have substantially similar annual returns (because they represent interests in the same portfolio of securities), Class M and Administrative Class performance would differ to the extent that Class M has higher expenses.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Daniel J. Ivascyn, Alfred Murata and Joshua Anderson. Mr. Ivascyn is Group Chief Investment Officer and a Managing Director of PIMCO. Messrs. Murata and Anderson are Managing Directors of PIMCO. Messrs. Ivascyn and Murata have managed the Portfolio since its inception in April 2016. Mr. Anderson has managed the Portfolio since July 2018.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio will also be subject to Emerging Markets Risk to the extent it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Distribution Rate Risk
Although the Portfolio may seek to maintain a level distribution rate, the Portfolio’s distribution rate may be affected by numerous factors, including but not limited to changes in realized and projected market returns, fluctuations in market interest rates, Portfolio performance, and other factors. For instance, during periods of low or declining interest rates, the Portfolio’s distributable income and dividend levels may decline for many reasons. There can be no assurance that a change in market conditions or other factors will not result in a change in the Portfolio’s distribution rate or that the rate will be sustainable in the future.
Contingent Convertible Securities Risk
Contingent convertible securities (“CoCos”) have no stated maturity, have fully discretionary coupons and are typically issued in the form of subordinated debt instruments. CoCos generally either convert into equity or have their principal written down upon the occurrence of certain triggering events (“triggers”) linked to regulatory capital thresholds or regulatory actions relating to the issuer’s continued viability. As a result, an investment by the Portfolio in CoCos is subject to the risk that coupon (i.e., interest) payments may be cancelled by the issuer or a regulatory authority in order to help the issuer absorb losses. An investment by the Portfolio in CoCos is also subject to the risk that, in the event of the liquidation, dissolution or winding-up of an issuer prior to a trigger event, the Portfolio’s rights and claims will generally rank junior to the claims of holders of the issuer’s other debt obligations. In addition, if CoCos held by the Portfolio are converted into the issuer’s underlying equity securities following a trigger event, the Portfolio’s holding may be further subordinated due to the conversion from a debt to equity instrument. Further, the value of an investment in CoCos is unpredictable and will be influenced by many factors and risks, including interest rate risk, credit risk, market risk and liquidity risk. An investment by the Portfolio in CoCos may result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.65% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Class M shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Class M shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Class M shares at the annual rate of 0.40% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager
Since
Recent Professional Experience
PIMCO Income
Joshua Anderson
7/18
Managing Director, PIMCO. Mr. Anderson is a portfolio manager focusing on global structured
credit investments. Prior to joining PIMCO in 2003, he was an analyst at Merrill Lynch covering
both the residential ABS and collateralized debt obligation sectors and was ranked as one of
the top analysts by Institutional Investor magazine. He was previously a portfolio manager at
Merrill Lynch Investment Managers.
PIMCO Income
Daniel J. Ivascyn
4/16*
Group Chief Investment Officer and Managing Director, PIMCO. Mr. Ivascyn joined PIMCO in
1998, previously having been associated with Bear Stearns in the asset backed securities
group, as well as T. Rowe Price and Fidelity Investments. He has investment experience since
1992 and holds an MBA in analytic finance from the University of Chicago Graduate School of
Business and a bachelor's degree in economics from Occidental College.
PIMCO Income
Alfred Murata
4/16*
Managing Director, PIMCO. Mr. Murata is a portfolio manager on the mortgage credit team.
Prior to joining PIMCO in 2001, he researched and implemented exotic equity and interest
rate derivatives at Nikko Financial Technologies.
*
Inception of the Portfolio.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Class M Shares
The Trust offers investors Class M shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Class M shares.
Distribution and/or Service (12b-1) Fees – Class M Shares. The Trust has adopted a Distribution and Servicing Plan for the Class M shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Class M shares and/or certain shareholder services to Class M shareholders at an annual rate of up to 0.25% of the Portfolio’s average daily net assets attributable to its Class M shares (the “Distribution Fee”).
The Distribution and Servicing Plan also permits the Portfolio to compensate the Distributor for providing or procuring administrative, recordkeeping, and other investor services at an annual rate with respect to the Portfolio not to exceed 0.20% of the average daily net assets of the Portfolio attributable to Class M shares (the “Servicing Fee”).
Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio’s Class M assets on an ongoing basis, over time they will increase the cost of an investment in Class M shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements. Class M shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Class M shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective
owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to

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Prospectus

insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase

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PIMCO Variable Insurance Trust

of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;

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bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of
the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be

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adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease
significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an

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obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored
mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the

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current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that
are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a

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smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable

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generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.
The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined

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by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,
PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for

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many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign
currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.

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Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with

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many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or
holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Real Estate Investment Trusts (REITs)
REITs are pooled investment vehicles that own, and usually operate, income-producing real estate. Some REITs also finance real estate. If a REIT meets certain requirements, including distributing to shareholders substantially all of its taxable income (other than net capital gains), then it is not taxed on the income distributed to shareholders. Therefore, REITs tend to pay higher dividends than other issuers.
REITs can be divided into three basic types: Equity REITs, Mortgage REITs and Hybrid REITs. Equity REITs invest the majority of their assets directly in real property. They derive their income primarily from rents received and any profits on the sale of their properties. Mortgage REITs invest the majority of their assets in real estate mortgages and derive

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most of their income from mortgage interest payments. As its name suggests, Hybrid REITs combine characteristics of both Equity REITs and Mortgage REITs.
An investment in a REIT, or in a real-estate linked derivative instrument linked to the value of a REIT, is subject to the risks that impact the value of the underlying properties of the REIT. These risks include loss to casualty or condemnation, and changes in supply and demand, interest rates, zoning laws, regulatory limitations on rents, property taxes and operating expenses. Other factors that may adversely affect REITs include poor performance by management of the REIT, changes to the tax laws, or failure by the REIT to qualify for tax-free distribution of income. REITs are also subject to default by borrowers and self-liquidation, and are heavily dependent on cash flow. Some REITs lack diversification because they invest in a limited number of properties, a narrow geographic area, or a single type of property. Mortgage REITs may be impacted by the quality of the credit extended.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules
and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good
faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Portfolio Distribution Rates
Although the Portfolio may seek to maintain level distributions, the Portfolio's distribution rates may be affected by numerous factors, including but not limited to changes in realized and projected market returns, fluctuations in market interest rates, Portfolio performance, and other factors. There can be no assurance that a change in market conditions or other factors will not result in a change in the Portfolio’s distribution rate or that the rate will be sustainable in the future.
For instance, during periods of low or declining interest rates, the Portfolio’s distributable income and dividend levels may decline for many reasons. For example, the Portfolio may have to deploy uninvested assets (whether from purchases of Portfolio shares, proceeds from matured, traded or called debt obligations or other sources) in new, lower yielding instruments. Additionally, payments from certain instruments that may be held by the Portfolio (such as variable and floating rate securities) may be negatively impacted by declining interest rates, which may also lead to a decline in the Portfolio’s distributable income and dividend levels.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income

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PIMCO Variable Insurance Trust

instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio managers' creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt

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normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. The information below reflects financial results for Administrative Class shares of the Portfolio, which are offered in a different prospectus. Class M shares of the Portfolio had not commenced operations during the period shown. The performance shown below differs from that which would have been achieved by Class M shares of the Portfolio to the extent that Class M has higher expenses than the Administrative Class. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Income Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$10.87
$0.36
$0.31
$0.67
$(0.50)
$(0.03)
$0.00
$(0.53)
12/31/2019
10.37
0.43
0.45
0.88
(0.38)
0.00
0.00
(0.38)
12/31/2018
10.74
0.40
(0.37)
0.03
(0.33)
(0.07)
0.00
(0.40)
12/31/2017
10.19
0.35
0.47
0.82
(0.27)
0.00
0.00
(0.27)
04/29/2016 - 12/31/2016
10.00
0.22
0.36
0.58
(0.37)
(0.02)
0.00
(0.39)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
*
Annualized
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.01
6.51%
$159,538
0.84%
0.84%
0.81%
0.81%
3.40%
390%
10.87
8.57
141,089
0.97
0.97
0.80
0.80
4.00
267
10.37
0.39
96,244
1.04
1.04
0.80
0.80
3.83
188
10.74
8.08
85,702
0.82
0.82
0.80
0.80
3.27
206
10.19
5.82
17,864
0.80 *
0.84 *
0.80 *
0.84 *
3.19 *
203

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2167F_043021


  
  
  
  
PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
INTERNATIONAL BOND PORTFOLIO
PIMCO International Bond Portfolio (Unhedged)
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


 
  
PIMCO International Bond Portfolio
(Unhedged)

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.75%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.08%
Total Annual Portfolio Operating Expenses
0.98%
1
“Other Expenses” include interest expense of 0.08%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.90% for Administrative Class shares.
Example. The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$100
$312
$542
$1,201
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 514% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments. The Portfolio will invest under normal circumstances in Fixed Income Instruments that are economically tied to at least three non-U.S. countries. The Portfolio’s investments in Fixed Income Instruments may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities.
PIMCO selects the Portfolio’s foreign country and currency compositions based on an evaluation of various factors, including, but not limited to, relative interest rates, exchange rates, monetary and fiscal policies, trade and current account balances. The average portfolio duration of this Portfolio normally varies within three years (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays Global Aggregate ex-USD (USD Unhedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 8.10 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest, without limitation, in securities and instruments that are economically tied to emerging market countries. The Portfolio is non-diversified, which means that it may invest its assets in a smaller number of issuers than a diversified fund.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buybacks or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.

1  PIMCO Variable Insurance Trust | Prospectus  

Prospectus

Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Small Portfolio Risk: the risk that a smaller Portfolio may not achieve investment or trading efficiencies. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares
Interest Rate Risk: the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk: the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk: the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk: the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk: the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk: the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk: the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk: the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk: the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk: the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk: the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk: the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk: the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk: the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments

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PIMCO International Bond Portfolio (Unhedged)

in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Issuer Non-Diversification Risk: the risk of focusing investments in a small number of issuers, including being more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Portfolios that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified”
Leveraging Risk: the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk: the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk: the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk: the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s broad-based securities market index is the Bloomberg Barclays Global Aggregate ex-USD (USD Unhedged) Index. The Bloomberg Barclays Global Aggregate ex-USD (USD Unhedged) Index provides a broad-based measure of the global investment-grade fixed income markets, excluding USD. The two major components of this index are the Pan-European Aggregate and the Asian-Pacific Aggregate Indices. The index also includes Eurodollar and Euro-Yen corporate bonds and Canadian Government securities. It is not possible to invest directly in an unmanaged index.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class   
Best Quarter
June 30, 2020
7.77%
Worst Quarter
March 31, 2020
-9.34%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Administrative Class Return
10.77%
5.38%
2.65%
Bloomberg Barclays Global Aggregate ex-USD (USD
Unhedged) Index (reflects no deductions for fees,
expenses or taxes)
10.11%
4.89%
1.99%

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Balls, Sachin Gupta and Lorenzo Pagani. Mr. Balls is CIO Global Fixed Income and a Managing Director of PIMCO. Mr. Gupta and Dr. Pagani are Managing Directors of PIMCO. Mr. Balls has managed the Portfolio since September 2014, Mr. Gupta has managed the Portfolio since September 2014, and Dr. Pagani has managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Small Portfolio Risk
A smaller Portfolio may not grow to or maintain an economically viable size to achieve investment or trading efficiencies, which may negatively impact performance and/or force the Portfolio to liquidate. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchases or redemptions.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases

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PIMCO Variable Insurance Trust

result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.

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PIMCO Variable Insurance Trust

In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

April 30, 2021 | PROSPECTUS  9

PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities the Portfolio may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Issuer Non-Diversification Risk
Focusing investments in a small number of issuers increases risk. The Portfolio which is “non-diversified” may invest a greater percentage of its assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified.” Portfolios that invest in a relatively small number of issuers are more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Some of those issuers also may present substantial credit or other risks.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objectives. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objectives.

April 30, 2021 | PROSPECTUS  11

PIMCO Variable Insurance Trust

Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.75% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee. The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee. The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager
Since
Recent Professional Experience
PIMCO International Bond (Unhedged)
Andrew Balls
9/14
CIO Global Fixed Income and Managing Director, PIMCO. He joined PIMCO in 2006 and is a
member of the Investment Committee and head of European portfolio management. Prior to
joining PIMCO, he spent eight years at the Financial Times, most recently as editor of the
U.S. Lex column and as chief economics correspondent in Washington, D.C.
PIMCO International Bond (Unhedged)
Sachin Gupta
9/14
Managing Director, PIMCO. Mr. Gupta joined PIMCO in 2003. He has previously managed
European LDI portfolios and served on the global portfolio management team in PIMCO's
Singapore office. Mr. Gupta has focused on investments in government bonds, sovereign credit
derivatives and interest rate derivatives across developed markets. Prior to joining PIMCO, Mr.
Gupta was in the fixed income and currency derivatives group at ABN AMRO Bank. He has
investment experience since 1998 and holds an MBA from XLRI, India.
PIMCO International Bond (Unhedged)
Lorenzo Pagani
9/14
Managing Director, PIMCO. Dr. Pagani joined PIMCO in 2004 and is a portfolio manager in
PIMCO's Munich office and head of the European government bond and European rates desk.
Prior to joining PIMCO, he was with the nuclear engineering department at the Massachusetts
Institute of Technology and with Procter & Gamble in Italy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

April 30, 2021 | PROSPECTUS  15

PIMCO Variable Insurance Trust

Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares. The Trust has adopted, pursuant to Rule 12b-1 under the the Investment Company Act of 1940, as amended (the “1940 Act”), , an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements. Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments. PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them

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Prospectus

or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the
Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;

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structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares.
U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary

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market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds
may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness

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of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same
underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate.

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For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be
less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”

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  Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a
portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including

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convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions. Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights. Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income
Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other

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collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities. The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the
security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future

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economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions. The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the
value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination. Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to

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withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives
strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.  A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.  Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.  The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.

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Liquidity Risk.   Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.   Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.  Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.  In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the
markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.  Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.

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ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling
a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

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Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio .
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

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Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to
additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO International Bond Portfolio (Unhedged)
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$10.05
$0.15
$0.86
$1.01
$(0.53)
$0.00
$0.00
$(0.53)
12/31/2019
9.58
0.19
0.48
0.67
(0.20)
0.00
0.00
(0.20)
12/31/2018
10.67
0.18
(0.60)
(0.42)
(0.50)
(0.14)
(0.03)
(0.67)
12/31/2017
9.78
0.13
0.93
1.06
(0.17)
0.00
0.00
(0.17)
12/31/2016
9.61
0.12
0.17
0.29
(0.12)
0.00
0.00
(0.12)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.53
10.77%
$10,504
0.98%
0.98%
0.90%
0.90%
1.54%
514%
10.05
7.02
9,826
1.08
1.08
0.90
0.90
1.95
299
9.58
(3.97)
9,420
1.02
1.02
0.90
0.90
1.72
197
10.67
10.83
8,468
0.99
0.99
0.90
0.90
1.26
216
9.78
3.00
7,731
0.95
0.95
0.90
0.90
1.19
419

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securities  are those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securities  are those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),  are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

  
  
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the SEC’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1856F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
INTERNATIONAL BOND PORTFOLIO
PIMCO International Bond Portfolio (Unhedged)
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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36
A-1


PIMCO International Bond Portfolio (Unhedged)

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.75%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.08%
Total Annual Portfolio Operating Expenses
1.08%
1
“Other Expenses” include interest expense of 0.08%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 1.00% for Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$110
$343
$595
$1,317
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 514% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments. The Portfolio will invest under normal circumstances in Fixed Income Instruments that are economically tied to at least three non-U.S. countries. The Portfolio’s investments in Fixed Income Instruments may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities.
PIMCO selects the Portfolio’s foreign country and currency compositions based on an evaluation of various factors, including, but not limited to, relative interest rates, exchange rates, monetary and fiscal policies, trade and current account balances. The average portfolio duration of this Portfolio normally varies within three years (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays Global Aggregate ex-USD (USD Unhedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 8.10 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest, without limitation, in securities and instruments that are economically tied to emerging market countries. The Portfolio is non-diversified, which means that it may invest its assets in a smaller number of issuers than a diversified fund.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buybacks or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Small Portfolio Risk:the risk that a smaller Portfolio may not achieve investment or trading efficiencies. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments

April 30, 2021 | PROSPECTUS  2

PIMCO International Bond Portfolio (Unhedged)

in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Issuer Non-Diversification Risk:the risk of focusing investments in a small number of issuers, including being more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Portfolios that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified”
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s broad-based securities market index is the Bloomberg Barclays Global Aggregate ex-USD (USD Unhedged) Index. The Bloomberg Barclays Global Aggregate ex-USD (USD Unhedged) Index provides a broad-based measure of the global investment-grade fixed income markets, excluding USD. The two major components of this index are the Pan-European Aggregate and the Asian-Pacific Aggregate Indices. The index also includes Eurodollar and Euro-Yen corporate bonds and Canadian Government securities. It is not possible to invest directly in an unmanaged index.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
June 30, 2020
7.75%
Worst Quarter
March 31, 2020
-9.36%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Advisor Class Return
10.66%
5.28%
2.53%
Bloomberg Barclays Global Aggregate ex-USD (USD
Unhedged) Index (reflects no deductions for fees,
expenses or taxes)
10.11%
4.89%
1.99%

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Balls, Sachin Gupta and Lorenzo Pagani. Mr. Balls is CIO Global Fixed Income and a Managing Director of PIMCO. Mr. Gupta and Dr. Pagani are Managing Directors of PIMCO. Mr. Balls has managed the Portfolio since September 2014, Mr. Gupta has managed the Portfolio since September 2014, and Dr. Pagani has managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Small Portfolio Risk
A smaller Portfolio may not grow to or maintain an economically viable size to achieve investment or trading efficiencies, which may negatively impact performance and/or force the Portfolio to liquidate. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchases or redemptions.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.

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PIMCO Variable Insurance Trust

In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities the Portfolio may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Issuer Non-Diversification Risk
Focusing investments in a small number of issuers increases risk. The Portfolio which is “non-diversified” may invest a greater percentage of its assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified.” Portfolios that invest in a relatively small number of issuers are more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Some of those issuers also may present substantial credit or other risks.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.

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PIMCO Variable Insurance Trust

Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.75% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.

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Prospectus

Individual Portfolio Managers
Portfolio
Portfolio Manager
Since
Recent Professional Experience
PIMCO International Bond (Unhedged)
Andrew Balls
9/14
CIO Global Fixed Income and Managing Director, PIMCO. He joined PIMCO in 2006 and is a
member of the Investment Committee and head of European portfolio management. Prior to
joining PIMCO, he spent eight years at the Financial Times, most recently as editor of the
U.S. Lex column and as chief economics correspondent in Washington, D.C.
PIMCO International Bond (Unhedged)
Sachin Gupta
9/14
Managing Director, PIMCO. Mr. Gupta joined PIMCO in 2003. He has previously managed
European LDI portfolios and served on the global portfolio management team in PIMCO's
Singapore office. Mr. Gupta has focused on investments in government bonds, sovereign credit
derivatives and interest rate derivatives across developed markets. Prior to joining PIMCO, Mr.
Gupta was in the fixed income and currency derivatives group at ABN AMRO Bank. He has
investment experience since 1998 and holds an MBA from XLRI, India.
PIMCO International Bond (Unhedged)
Lorenzo Pagani
9/14
Managing Director, PIMCO. Dr. Pagani joined PIMCO in 2004 and is a portfolio manager in
PIMCO's Munich office and head of the European government bond and European rates desk.
Prior to joining PIMCO, he was with the nuclear engineering department at the Massachusetts
Institute of Technology and with Procter & Gamble in Italy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

April 30, 2021 | PROSPECTUS  15

PIMCO Variable Insurance Trust

Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

April 30, 2021 | PROSPECTUS  17

PIMCO Variable Insurance Trust

thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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Prospectus

these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;

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inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition,

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imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond
program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the

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volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools
because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.

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Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid
insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other

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asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or
losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy

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common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical

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service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.

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Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which
involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro

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cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates,
commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to

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the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited
to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.

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Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will
decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to

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$1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established
secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In

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PIMCO Variable Insurance Trust

such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in
achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or

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Prospectus

unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO International Bond Portfolio (Unhedged)
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$10.05
$0.14
$0.86
$1.00
$(0.52)
$0.00
$0.00
$(0.52)
12/31/2019
9.58
0.18
0.48
0.66
(0.19)
0.00
0.00
(0.19)
12/31/2018
10.67
0.17
(0.60)
(0.43)
(0.49)
(0.14)
(0.03)
(0.66)
12/31/2017
9.78
0.12
0.93
1.05
(0.16)
0.00
0.00
(0.16)
12/31/2016
9.61
0.11
0.17
0.28
(0.11)
0.00
0.00
(0.11)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.53
10.66%
$20,408
1.08%
1.08%
1.00%
1.00%
1.43%
514%
10.05
6.92
19,624
1.18
1.18
1.00
1.00
1.85
299
9.58
(4.07)
20,278
1.12
1.12
1.00
1.00
1.61
197
10.67
10.72
22,498
1.09
1.09
1.00
1.00
1.14
216
9.78
2.90
22,506
1.05
1.05
1.00
1.00
1.08
419

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

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PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1946F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
INTERNATIONAL BOND PORTFOLIO
PIMCO International Bond Portfolio (Unhedged)
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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1
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35
A-1


PIMCO International Bond Portfolio (Unhedged)

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.75%
Other Expenses(1)
0.08%
Total Annual Portfolio Operating Expenses
0.83%
1
“Other Expenses” include interest expense of 0.08%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.75% for Institutional Class shares.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$85
$265
$460
$1,025
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 514% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments. The Portfolio will invest under normal circumstances in Fixed Income Instruments that are economically tied to at least three non-U.S. countries. The Portfolio’s investments in Fixed Income Instruments may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities.
PIMCO selects the Portfolio’s foreign country and currency compositions based on an evaluation of various factors, including, but not limited to, relative interest rates, exchange rates, monetary and fiscal policies, trade and current account balances. The average portfolio duration of this Portfolio normally varies within three years (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays Global Aggregate ex-USD (USD Unhedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 8.10 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest, without limitation, in securities and instruments that are economically tied to emerging market countries. The Portfolio is non-diversified, which means that it may invest its assets in a smaller number of issuers than a diversified fund.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buybacks or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Small Portfolio Risk:the risk that a smaller Portfolio may not achieve investment or trading efficiencies. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments

April 30, 2021 | PROSPECTUS  2

PIMCO International Bond Portfolio (Unhedged)

in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Issuer Non-Diversification Risk:the risk of focusing investments in a small number of issuers, including being more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Portfolios that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified”
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s broad-based securities market index is the Bloomberg Barclays Global Aggregate ex-USD (USD Unhedged) Index. The Bloomberg Barclays Global Aggregate ex-USD (USD Unhedged) Index provides a broad-based measure of the global investment-grade fixed income markets, excluding USD. The two major components of this index are the Pan-European Aggregate and the Asian-Pacific Aggregate Indices. The index also includes Eurodollar and Euro-Yen corporate bonds and Canadian Government securities. It is not possible to invest directly in an unmanaged index.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class
Best Quarter
June 30, 2020
7.81%
Worst Quarter
March 31, 2020
-9.30%

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Institutional Class Return
10.93%
5.52%
1.96%
4/30/2012
Bloomberg Barclays Global Aggregate
ex-USD (USD Unhedged) Index (reflects
no deductions for fees, expenses or
taxes)
10.11%
4.89%
1.52%
 
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Balls, Sachin Gupta and Lorenzo Pagani. Mr. Balls is CIO Global Fixed Income and a Managing Director of PIMCO. Mr. Gupta and Dr. Pagani are Managing Directors of PIMCO. Messrs. Balls and Gupta and Dr. Pagani have jointly and primarily managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Small Portfolio Risk
A smaller Portfolio may not grow to or maintain an economically viable size to achieve investment or trading efficiencies, which may negatively impact performance and/or force the Portfolio to liquidate. Additionally, a smaller Portfolio may be more adversely affected by large purchases or redemptions of Portfolio shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchases or redemptions.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases

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result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.
Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.

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In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.

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In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities, illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities the Portfolio may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Issuer Non-Diversification Risk
Focusing investments in a small number of issuers increases risk. The Portfolio which is “non-diversified” may invest a greater percentage of its assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified.” Portfolios that invest in a relatively small number of issuers are more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Some of those issuers also may present substantial credit or other risks.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.

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PIMCO Variable Insurance Trust

Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.75% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager
Since
Recent Professional Experience
PIMCO International Bond (Unhedged)
Andrew Balls
9/14
CIO Global Fixed Income and Managing Director, PIMCO. He joined PIMCO in 2006 and is a
member of the Investment Committee and head of European portfolio management. Prior to
joining PIMCO, he spent eight years at the Financial Times, most recently as editor of the
U.S. Lex column and as chief economics correspondent in Washington, D.C.
PIMCO International Bond (Unhedged)
Sachin Gupta
9/14
Managing Director, PIMCO. Mr. Gupta joined PIMCO in 2003. He has previously managed
European LDI portfolios and served on the global portfolio management team in PIMCO's
Singapore office. Mr. Gupta has focused on investments in government bonds, sovereign credit
derivatives and interest rate derivatives across developed markets. Prior to joining PIMCO, Mr.
Gupta was in the fixed income and currency derivatives group at ABN AMRO Bank. He has
investment experience since 1998 and holds an MBA from XLRI, India.
PIMCO International Bond (Unhedged)
Lorenzo Pagani
9/14
Managing Director, PIMCO. Dr. Pagani joined PIMCO in 2004 and is a portfolio manager in
PIMCO's Munich office and head of the European government bond and European rates desk.
Prior to joining PIMCO, he was with the nuclear engineering department at the Massachusetts
Institute of Technology and with Procter & Gamble in Italy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

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Prospectus

From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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PIMCO Variable Insurance Trust

per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder

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purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.

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Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by

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the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may
participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying

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property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real
estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and

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equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign
governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.

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Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.

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Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political
subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes

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in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which
they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or

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otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant
foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but

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only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in
“Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are

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relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies
involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.

April 30, 2021 | PROSPECTUS  31

PIMCO Variable Insurance Trust

Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled
vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a
portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is non-fundamental and may be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not

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evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents,
custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

34  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO International Bond Portfolio (Unhedged)
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$10.05
$0.16
$0.87
$1.03
$(0.55)
$0.00
$0.00
$(0.55)
12/31/2019
9.58
0.21
0.47
0.68
(0.21)
0.00
0.00
(0.21)
12/31/2018
10.67
0.19
(0.60)
(0.41)
(0.51)
(0.14)
(0.03)
(0.68)
12/31/2017
9.78
0.14
0.93
1.07
(0.18)
0.00
0.00
(0.18)
12/31/2016
9.61
0.14
0.17
0.31
(0.14)
0.00
0.00
(0.14)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.53
10.93%
$12
0.83%
0.83%
0.75%
0.75%
1.68%
514%
10.05
7.17
11
0.93
0.93
0.75
0.75
2.10
299
9.58
(3.85)
10
0.87
0.87
0.75
0.75
1.85
197
10.67
10.96
10
0.84
0.84
0.75
0.75
1.37
216
9.78
3.15
9
0.80
0.80
0.75
0.75
1.34
419

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2052F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
INTERNATIONAL BOND PORTFOLIO
PIMCO International Bond Portfolio (U.S. Dollar-Hedged)
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO International Bond Portfolio (U.S. Dollar-Hedged)

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.75%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.94%
1
“Other Expenses” include interest expense of 0.04%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.90% for Administrative Class shares.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$96
$300
$520
$1,155
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 512% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments. The Portfolio will invest under normal circumstances in Fixed Income Instruments that are economically tied to at least three non-U.S. countries. The Portfolio’s investments in Fixed Income Instruments may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
PIMCO selects the Portfolio’s foreign country and currency compositions based on an evaluation of various factors, including, but not limited to, relative interest rates, exchange rates, monetary and fiscal policies, trade and current account balances. The Portfolio may invest, without limitation, in securities and instruments that are economically tied to emerging market countries. The average portfolio duration of this Portfolio normally varies within three years (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays Global Aggregate ex-USD (USD Hedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 8.10 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio is non-diversified, which means that it may invest its assets in a smaller number of issuers than a diversified fund.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the
underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Issuer Non-Diversification Risk:the risk of focusing investments in a small number of issuers, including being more susceptible to risks

April 30, 2021 | PROSPECTUS  2

PIMCO International Bond Portfolio (U.S. Dollar-Hedged)

associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Portfolios that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified”
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee
waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s broad-based securities market index is the Bloomberg Barclays Global Aggregate ex-USD (USD Hedged) Index. The Bloomberg Barclays Global Aggregate ex-USD (USD Hedged) Index provides a broad-based measure of the global investment-grade fixed income markets, excluding USD. The two major components of this index are the Pan-European Aggregate and the Asian-Pacific Aggregate Indices. The index also includes Eurodollar and Euro-Yen corporate bonds and Canadian Government securities. It is not possible to invest directly in an unmanaged index.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
September 30, 2012
5.16%
Worst Quarter
June 30, 2015
-4.20%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Administrative Class Return
5.56%
4.77%
5.28%
Bloomberg Barclays Global Aggregate ex-USD (USD
Hedged) Index (reflects no deductions for fees, expenses
or taxes)
3.94%
4.40%
4.35%

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Balls, Sachin Gupta and Lorenzo Pagani. Mr. Balls is CIO Global Fixed Income and a Managing Director of PIMCO. Mr. Gupta and Dr. Pagani are Managing Directors of PIMCO. Messrs. Balls and Gupta and Dr. Pagani have jointly and primarily managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

April 30, 2021 | PROSPECTUS  7

PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

April 30, 2021 | PROSPECTUS  9

PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities the Portfolio may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Issuer Non-Diversification Risk
Focusing investments in a small number of issuers increases risk. The Portfolio which is “non-diversified” may invest a greater percentage of its assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified.” Portfolios that invest in a relatively small number of issuers are more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Some of those issuers also may present substantial credit or other risks.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.

April 30, 2021 | PROSPECTUS  11

PIMCO Variable Insurance Trust

Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.75% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager
Since
Recent Professional Experience
PIMCO International Bond (U.S. Dollar-Hedged)
Andrew Balls
9/14
CIO Global Fixed Income and Managing Director, PIMCO. He joined PIMCO in 2006 and is a
member of the Investment Committee and head of European portfolio management. Prior to
joining PIMCO, he spent eight years at the Financial Times, most recently as editor of the
U.S. Lex column and as chief economics correspondent in Washington, D.C.
PIMCO International Bond (U.S. Dollar-Hedged)
Sachin Gupta
9/14
Managing Director, PIMCO. Mr. Gupta joined PIMCO in 2003. He has previously managed
European LDI portfolios and served on the global portfolio management team in PIMCO's
Singapore office. Mr. Gupta has focused on investments in government bonds, sovereign credit
derivatives and interest rate derivatives across developed markets. Prior to joining PIMCO, Mr.
Gupta was in the fixed income and currency derivatives group at ABN AMRO Bank. He has
investment experience since 1998 and holds an MBA from XLRI, India.
PIMCO International Bond (U.S. Dollar-Hedged)
Lorenzo Pagani
9/14
Managing Director, PIMCO. Dr. Pagani joined PIMCO in 2004 and is a portfolio manager in
PIMCO's Munich office and head of the European government bond and European rates desk.
Prior to joining PIMCO, he was with the nuclear engineering department at the Massachusetts
Institute of Technology and with Procter & Gamble in Italy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

April 30, 2021 | PROSPECTUS  15

PIMCO Variable Insurance Trust

Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the the Investment Company Act of 1940, as amended (the “1940 Act”), an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them

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Prospectus

or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the
Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;

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structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares.
U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary

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market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds
may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness

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of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same
underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate.

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For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be
less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”

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  Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a
portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including

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convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income
Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other

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collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the
security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future

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Prospectus

economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the
value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to

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withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives
strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.

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Prospectus

Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in the Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the
markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.

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ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling
a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

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Prospectus

Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

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Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to
additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO International Bond Portfolio (U.S. Dollar-Hedged)
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$11.32
$0.16
$0.44
$0.60
$(0.68)
$0.00
$0.00
$(0.68)
12/31/2019
10.84
0.21
0.55
0.76
(0.20)
(0.08)
0.00
(0.28)
12/31/2018
10.79
0.18
0.05
0.23
(0.14)
(0.04)
0.00
(0.18)
12/31/2017
11.02
0.13
0.17
0.30
(0.53)
0.00
0.00
(0.53)
12/31/2016
10.54
0.14
0.54
0.68
(0.16)
(0.04)
0.00
(0.20)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.24
5.56%
$78,210
0.94%
0.94%
0.90%
0.90%
1.44%
512%
11.32
7.01
79,540
1.01
1.01
0.90
0.90
1.83
272
10.84
2.12
78,640
0.96
0.96
0.90
0.90
1.70
185
10.79
2.76
76,989
0.93
0.93
0.90
0.90
1.21
158
11.02
6.48
64,537
0.93
0.93
0.90
0.90
1.31
330

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0335F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
INTERNATIONAL BOND PORTFOLIO
PIMCO International Bond Portfolio (U.S. Dollar-Hedged)
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
Page
1
1
5
12
14
16
17
19
20
20
36
A-1


PIMCO International Bond Portfolio (U.S. Dollar-Hedged)

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.75%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
1.04%
1
“Other Expenses” include interest expense of 0.04%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 1.00% for Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$106
$331
$574
$1,271
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 512% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments. The Portfolio will invest under normal circumstances in Fixed Income Instruments that are economically tied to at least three non-U.S. countries. The Portfolio’s investments in Fixed Income Instruments may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
PIMCO selects the Portfolio’s foreign country and currency compositions based on an evaluation of various factors, including, but not limited to, relative interest rates, exchange rates, monetary and fiscal policies, trade and current account balances. The Portfolio may invest, without limitation, in securities and instruments that are economically tied to emerging market countries. The average portfolio duration of this Portfolio normally varies within three years (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays Global Aggregate ex-USD (USD Hedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 8.10 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio is non-diversified, which means that it may invest its assets in a smaller number of issuers than a diversified fund.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the
underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Issuer Non-Diversification Risk:the risk of focusing investments in a small number of issuers, including being more susceptible to risks

April 30, 2021 | PROSPECTUS  2

PIMCO International Bond Portfolio (U.S. Dollar-Hedged)

associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Portfolios that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified”
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee
waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s broad-based securities market index is the Bloomberg Barclays Global Aggregate ex-USD (USD Hedged) Index. The Bloomberg Barclays Global Aggregate ex-USD (USD Hedged) Index provides a broad-based measure of the global investment-grade fixed income markets, excluding USD. The two major components of this index are the Pan-European Aggregate and the Asian-Pacific Aggregate Indices. The index also includes Eurodollar and Euro-Yen corporate bonds and Canadian Government securities. It is not possible to invest directly in an unmanaged index.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
June 30, 2020
3.77%
Worst Quarter
June 30, 2015
-4.23%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
Since
Inception
Inception
Date
Advisor Class Return
5.45%
4.66%
4.60%
4/30/2014
Bloomberg Barclays Global Aggregate
ex-USD (USD Hedged) Index (reflects no
deductions for fees, expenses or taxes)
3.94%
4.40%
4.37%
 

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Balls, Sachin Gupta and Lorenzo Pagani. Mr. Balls is CIO Global Fixed Income and a Managing Director of PIMCO. Mr. Gupta and Dr. Pagani are Managing Directors of PIMCO. Messrs. Balls and Gupta and Dr. Pagani have jointly and primarily managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Issuer Non-Diversification Risk
Focusing investments in a small number of issuers increases risk. The Portfolio which is “non-diversified” may invest a greater percentage of its assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified.” Portfolios that invest in a relatively small number of issuers are more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Some of those issuers also may present substantial credit or other risks.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.

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Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.75% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager
Since
Recent Professional Experience
PIMCO International Bond (U.S. Dollar-Hedged)
Andrew Balls
9/14
CIO Global Fixed Income and Managing Director, PIMCO. He joined PIMCO in 2006 and is a
member of the Investment Committee and head of European portfolio management. Prior to
joining PIMCO, he spent eight years at the Financial Times, most recently as editor of the
U.S. Lex column and as chief economics correspondent in Washington, D.C.
PIMCO International Bond (U.S. Dollar-Hedged)
Sachin Gupta
9/14
Managing Director, PIMCO. Mr. Gupta joined PIMCO in 2003. He has previously managed
European LDI portfolios and served on the global portfolio management team in PIMCO's
Singapore office. Mr. Gupta has focused on investments in government bonds, sovereign credit
derivatives and interest rate derivatives across developed markets. Prior to joining PIMCO, Mr.
Gupta was in the fixed income and currency derivatives group at ABN AMRO Bank. He has
investment experience since 1998 and holds an MBA from XLRI, India.
PIMCO International Bond (U.S. Dollar-Hedged)
Lorenzo Pagani
9/14
Managing Director, PIMCO. Dr. Pagani joined PIMCO in 2004 and is a portfolio manager in
PIMCO's Munich office and head of the European government bond and European rates desk.
Prior to joining PIMCO, he was with the nuclear engineering department at the Massachusetts
Institute of Technology and with Procter & Gamble in Italy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

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Prospectus

From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

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circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;

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inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition,

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imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond
program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the

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volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools
because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.

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Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid
insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other

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asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or
losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy

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common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical

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service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.

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Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which
involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro

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cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates,
commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to

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the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited
to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.

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Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will
decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to

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$1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established
secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In

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PIMCO Variable Insurance Trust

such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in
achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or

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Prospectus

unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO International Bond Portfolio (U.S. Dollar-Hedged)
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$11.32
$0.15
$0.44
$0.59
$(0.67)
$0.00
$0.00
$(0.67)
12/31/2019
10.84
0.19
0.56
0.75
(0.19)
(0.08)
0.00
(0.27)
12/31/2018
10.79
0.17
0.05
0.22
(0.13)
(0.04)
0.00
(0.17)
12/31/2017
11.02
0.12
0.17
0.29
(0.52)
0.00
0.00
(0.52)
12/31/2016
10.54
0.13
0.54
0.67
(0.15)
(0.04)
0.00
(0.19)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.24
5.45%
$488,470
1.04%
1.04%
1.00%
1.00%
1.34%
512%
11.32
6.90
477,388
1.11
1.11
1.00
1.00
1.73
272
10.84
2.02
444,881
1.06
1.06
1.00
1.00
1.59
185
10.79
2.66
431,545
1.03
1.03
1.00
1.00
1.11
158
11.02
6.37
341,567
1.03
1.03
1.00
1.00
1.21
330

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

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PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT2101F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
INTERNATIONAL BOND PORTFOLIO
PIMCO International Bond Portfolio (U.S. Dollar-Hedged)
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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35
A-1


PIMCO International Bond Portfolio (U.S. Dollar-Hedged)

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.75%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.79%
1
“Other Expenses” include interest expense of 0.04%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.75% for Institutional Class shares.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$81
$252
$439
$978
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 512% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in Fixed Income Instruments. The Portfolio will invest under normal circumstances in Fixed Income Instruments that are economically tied to at least three non-U.S. countries. The Portfolio’s investments in Fixed Income Instruments may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
PIMCO selects the Portfolio’s foreign country and currency compositions based on an evaluation of various factors, including, but not limited to, relative interest rates, exchange rates, monetary and fiscal policies, trade and current account balances. The Portfolio may invest, without limitation, in securities and instruments that are economically tied to emerging market countries. The average portfolio duration of this Portfolio normally varies within three years (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays Global Aggregate ex-USD (USD Hedged) Index, as calculated by PIMCO, which as of February 28, 2021 was 8.10 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. The Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio is non-diversified, which means that it may invest its assets in a smaller number of issuers than a diversified fund.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the
underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Issuer Non-Diversification Risk:the risk of focusing investments in a small number of issuers, including being more susceptible to risks

April 30, 2021 | PROSPECTUS  2

PIMCO International Bond Portfolio (U.S. Dollar-Hedged)

associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Portfolios that are “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than portfolios that are “diversified”
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee
waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Portfolio’s broad-based securities market index is the Bloomberg Barclays Global Aggregate ex-USD (USD Hedged) Index. The Bloomberg Barclays Global Aggregate ex-USD (USD Hedged) Index provides a broad-based measure of the global investment-grade fixed income markets, excluding USD. The two major components of this index are the Pan-European Aggregate and the Asian-Pacific Aggregate Indices. The index also includes Eurodollar and Euro-Yen corporate bonds and Canadian Government securities. It is not possible to invest directly in an unmanaged index.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class
Best Quarter
September 30, 2012
5.20%
Worst Quarter
June 30, 2015
-4.17%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Institutional Class Return
5.72%
4.92%
5.44%
Bloomberg Barclays Global Aggregate ex-USD (USD
Hedged) Index (reflects no deductions for fees, expenses
or taxes)
3.94%
4.40%
4.35%

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Andrew Balls, Sachin Gupta and Lorenzo Pagani. Mr. Balls is CIO Global Fixed Income and a Managing Director of PIMCO. Mr. Gupta and Dr. Pagani are Managing Directors of PIMCO. Messrs. Balls and Gupta and Dr. Pagani have jointly and primarily managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Issuer Non-Diversification Risk
Focusing investments in a small number of issuers increases risk. The Portfolio, which is “non-diversified” may invest a greater percentage of their assets in the securities of a single issuer (such as bonds issued by a particular state) than a portfolio that is “diversified.” Portfolios that invest in a relatively small number of issuers are more susceptible to risks associated with a single economic, political or regulatory occurrence than a more diversified portfolio might be. Some of those issuers also may present substantial credit or other risks.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.

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PIMCO Variable Insurance Trust

Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.75% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager
Since
Recent Professional Experience
PIMCO International Bond (U.S. Dollar-Hedged)
Andrew Balls
9/14
CIO Global Fixed Income and Managing Director, PIMCO. He joined PIMCO in 2006 and is a
member of the Investment Committee and head of European portfolio management. Prior to
joining PIMCO, he spent eight years at the Financial Times, most recently as editor of the
U.S. Lex column and as chief economics correspondent in Washington, D.C.
PIMCO International Bond (U.S. Dollar-Hedged)
Sachin Gupta
9/14
Managing Director, PIMCO. Mr. Gupta joined PIMCO in 2003. He has previously managed
European LDI portfolios and served on the global portfolio management team in PIMCO's
Singapore office. Mr. Gupta has focused on investments in government bonds, sovereign credit
derivatives and interest rate derivatives across developed markets. Prior to joining PIMCO, Mr.
Gupta was in the fixed income and currency derivatives group at ABN AMRO Bank. He has
investment experience since 1998 and holds an MBA from XLRI, India.
PIMCO International Bond (U.S. Dollar-Hedged)
Lorenzo Pagani
9/14
Managing Director, PIMCO. Dr. Pagani joined PIMCO in 2004 and is a portfolio manager in
PIMCO's Munich office and head of the European government bond and European rates desk.
Prior to joining PIMCO, he was with the nuclear engineering department at the Massachusetts
Institute of Technology and with Procter & Gamble in Italy.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

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Prospectus

From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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PIMCO Variable Insurance Trust

per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder

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purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.

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Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by

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the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may
participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying

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property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real
estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and

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equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign
governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.

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Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.

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Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political
subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes

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in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which
they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or

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otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant
foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but

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only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in
“Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are

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Prospectus

relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies
involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.

April 30, 2021 | PROSPECTUS  31

PIMCO Variable Insurance Trust

Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled
vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a
portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objective and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment. The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not

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evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents,
custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

34  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO International Bond Portfolio (U.S. Dollar-Hedged)
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$11.32
$0.17
$0.45
$0.62
$(0.70)
$0.00
$0.00
$(0.70)
12/31/2019
10.84
0.22
0.55
0.77
(0.21)
(0.08)
0.00
(0.29)
12/31/2018
10.79
0.20
0.05
0.25
(0.16)
(0.04)
0.00
(0.20)
12/31/2017
11.02
0.15
0.17
0.32
(0.55)
0.00
0.00
(0.55)
12/31/2016
10.54
0.16
0.54
0.70
(0.18)
(0.04)
0.00
(0.22)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.24
5.72%
$84,623
0.79%
0.79%
0.75%
0.75%
1.52%
512%
11.32
7.17
9,105
0.86
0.86
0.75
0.75
1.98
272
10.84
2.27
7,483
0.81
0.81
0.75
0.75
1.85
185
10.79
2.92
6,705
0.78
0.78
0.75
0.75
1.37
158
11.02
6.63
5,045
0.78
0.78
0.75
0.75
1.46
330

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0595F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
LONG DURATION BOND PORTFOLIO
PIMCO Long-Term U.S. Government Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Long-Term U.S. Government Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.475%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.22%
Total Annual Portfolio Operating Expenses
0.845%
1
“Other Expenses” include interest expense of 0.22%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.625% for Administrative Class shares.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$86
$270
$469
$1,043
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 251% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in a diversified portfolio of fixed income securities that are issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”), which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. Assets not invested in U.S. Government Securities may be invested in other types of Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. While PIMCO may invest in derivatives at any time it deems appropriate, it will generally do so when it believes that U.S. Government Securities are overvalued relative to derivative instruments. This Portfolio will normally have a minimum average portfolio duration of eight years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. In addition, the dollar-weighted average portfolio maturity of the Portfolio, under normal circumstances, is expected to be more than ten years.
The Portfolio’s investments in Fixed Income Instruments are limited to those of investment grade U.S. dollar-denominated securities of U.S. issuers that are rated at least A by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”), or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In addition, the Portfolio may only invest up to 10% of its total assets in securities rated A by Moody’s, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality and may only invest up to 25% of its total assets in securities rated Aa by Moody’s, or equivalently rated by S&P or Fitch or, if unrated, determined by PIMCO to be of comparable quality.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Barclays Long-Term Treasury Index consists of U.S. Treasury issues with maturities of 10 or more years.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.

April 30, 2021 | PROSPECTUS  2

PIMCO Long-Term U.S. Government Portfolio

Calendar Year Total Returns — Administrative Class
Best Quarter
September 30, 2011
22.46%
Worst Quarter
December 31, 2016
-12.17%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Administrative Class Return
17.39%
7.33%
7.31%
Bloomberg Barclays Long-Term Treasury Index (reflects
no deductions for fees, expenses or taxes)
17.70%
7.85%
7.80%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Mike Cudzil and Steve Rodosky. Messrs. Cudzil and Rodosky are Managing Directors of PIMCO. Mr. Cudzil has managed the Portfolio since February 2016. Mr. Rodosky has managed the Portfolio since July 2007.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

3  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

4  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests. These factors include the possibility that the Portfolio's commodity derivatives positions may have different roll dates, reset dates or contract months than those specified in a particular commodity index. By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

April 30, 2021 | PROSPECTUS  7

PIMCO Variable Insurance Trust

Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

8  Prospectus | PIMCO Variable Insurance Trust

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.475% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.225% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.

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Prospectus

Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Long-Term U.S. Government
Mike Cudzil
2/16
Managing Director, PIMCO. Mr. Cudzil is a portfolio manager and mortgage specialist. Prior
to joining PIMCO in 2012, he worked as a managing director and head of pass-through
trading at Nomura.
PIMCO Long-Term U.S. Government
Steve Rodosky
7/07
Managing Director, PIMCO. Mr. Rodosky joined PIMCO in 2001 and specializes in portfolio
management of treasuries, agencies and futures.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”), an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

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Prospectus

conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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PIMCO Variable Insurance Trust

fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Prospectus

Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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PIMCO Variable Insurance Trust

Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them

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or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the
Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;

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structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares.
U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary

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market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds
may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness

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of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same
underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate.

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For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit
spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.

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The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The
Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.

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Prospectus

In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase
agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.

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PIMCO Variable Insurance Trust

CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative
instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or

24  Prospectus | PIMCO Variable Insurance Trust

Prospectus

price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time
when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use

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PIMCO Variable Insurance Trust

solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and

26  Prospectus | PIMCO Variable Insurance Trust

Prospectus

reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the
Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.

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PIMCO Variable Insurance Trust

Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Long-Term U.S. Government Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$12.90
$0.24
$2.01
$2.25
$(0.25)
$(0.13)
$0.00
$(0.38)
12/31/2019
11.62
0.25
1.29
1.54
(0.26)
0.00
0.00
(0.26)
12/31/2018
12.25
0.27
(0.57)
(0.30)
(0.28)
(0.05)
0.00
(0.33)
12/31/2017
11.49
0.27
0.75
1.02
(0.26)
0.00
0.00
(0.26)
12/31/2016
11.64
0.27
(0.17)
0.10
(0.25)
0.00
0.00
(0.25)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

29  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$14.77
17.39%
$500,164
0.845%
0.845%
0.625%
0.625%
1.61%
251%
12.90
13.32
407,059
0.745
0.745
0.625
0.625
2.01
129
11.62
(2.38)
268,621
0.985
0.985
0.625
0.625
2.36
164
12.25
8.95
249,568
0.765
0.765
0.625
0.625
2.27
107
11.49
0.67
236,801
0.715
0.715
0.625
0.625
2.12
135

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

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PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

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Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

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PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

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PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0341F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
LONG DURATION BOND PORTFOLIO
PIMCO Long-Term U.S. Government Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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PIMCO Long-Term U.S. Government Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.475%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.22%
Total Annual Portfolio Operating Expenses
0.945%
1
“Other Expenses” include interest expense of 0.22%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.725% for Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$96
$301
$523
$1,161
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 251% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in a diversified portfolio of fixed income securities that are issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”), which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. Assets not invested in U.S. Government Securities may be invested in other types of Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. While PIMCO may invest in derivatives at any time it deems appropriate, it will generally do so when it believes that U.S. Government Securities are overvalued relative to derivative instruments. This Portfolio will normally have a minimum average portfolio duration of eight years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. In addition, the dollar-weighted average portfolio maturity of the Portfolio, under normal circumstances, is expected to be more than ten years.
The Portfolio’s investments in Fixed Income Instruments are limited to those of investment grade U.S. dollar-denominated securities of U.S. issuers that are rated at least A by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”), or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In addition, the Portfolio may only invest up to 10% of its total assets in securities rated A by Moody’s, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality and may only invest up to 25% of its total assets in securities rated Aa by Moody’s, or equivalently rated by S&P or Fitch or, if unrated, determined by PIMCO to be of comparable quality.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Barclays Long-Term Treasury Index consists of U.S. Treasury issues with maturities of 10 or more years.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.

April 30, 2021 | PROSPECTUS  2

PIMCO Long-Term U.S. Government Portfolio

Calendar Year Total Returns — Advisor Class
Best Quarter
September 30, 2011
22.43%
Worst Quarter
December 31, 2016
-12.19%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Advisor Class Return
17.28%
7.22%
7.19%
Bloomberg Barclays Long-Term Treasury Index (reflects
no deductions for fees, expenses or taxes)
17.70%
7.85%
7.80%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Mike Cudzil and Steve Rodosky. Messrs. Cudzil and Rodosky are Managing Directors of PIMCO. Mr. Cudzil has managed the Portfolio since February 2016. Mr. Rodosky has managed the Portfolio since July 2007.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

3  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

4  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests. These factors include the possibility that the Portfolio's commodity derivatives positions may have different roll dates, reset dates or contract months than those specified in a particular commodity index. By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.475% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.225% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Long-Term U.S. Government
Mike Cudzil
2/16
Managing Director, PIMCO. Mr. Cudzil is a portfolio manager and mortgage specialist. Prior
to joining PIMCO in 2012, he worked as a managing director and head of pass-through
trading at Nomura.
PIMCO Long-Term U.S. Government
Steve Rodosky
7/07
Managing Director, PIMCO. Mr. Rodosky joined PIMCO in 2001 and specializes in portfolio
management of treasuries, agencies and futures.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

12  Prospectus | PIMCO Variable Insurance Trust

Prospectus

From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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PIMCO Variable Insurance Trust

thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;

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inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition,

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imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond
program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the

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volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools
because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.

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Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate
instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation

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decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value
of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.

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Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio
and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks

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associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives

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for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled

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vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no
added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a

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portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not
evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents,

April 30, 2021 | PROSPECTUS  27

PIMCO Variable Insurance Trust

custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

28  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Long-Term U.S. Government Portfolio
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$12.90
$0.23
$2.01
$2.24
$(0.24)
$(0.13)
$0.00
$(0.37)
12/31/2019
11.62
0.24
1.29
1.53
(0.25)
0.00
0.00
(0.25)
12/31/2018
12.25
0.26
(0.58)
(0.32)
(0.26)
(0.05)
0.00
(0.31)
12/31/2017
11.49
0.26
0.75
1.01
(0.25)
0.00
0.00
(0.25)
12/31/2016
11.64
0.25
(0.17)
0.08
(0.23)
0.00
0.00
(0.23)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

29  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$14.77
17.28%
$39,831
0.945%
0.945%
0.725%
0.725%
1.50%
251%
12.90
13.21
25,866
0.845
0.845
0.725
0.725
1.92
129
11.62
(2.48)
22,243
1.085
1.085
0.725
0.725
2.26
164
12.25
8.85
23,003
0.865
0.865
0.725
0.725
2.17
107
11.49
0.57
19,143
0.815
0.815
0.725
0.725
2.02
135

April 30, 2021 | PROSPECTUS  30

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1957F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
LONG DURATION BOND PORTFOLIO
PIMCO Long-Term U.S. Government Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Long-Term U.S. Government Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.475%
Other Expenses(1)
0.22%
Total Annual Portfolio Operating Expenses
0.695%
1
“Other Expenses” include interest expense of 0.22%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.475% for Institutional Class shares.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$71
$222
$387
$865
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 251% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its assets in a diversified portfolio of fixed income securities that are issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”), which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. Assets not invested in U.S. Government Securities may be invested in other types of Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. While PIMCO may invest in derivatives at any time it deems appropriate, it will generally do so when it believes that U.S. Government Securities are overvalued relative to derivative instruments. This Portfolio will normally have a minimum average portfolio duration of eight years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. In addition, the dollar-weighted average portfolio maturity of the Portfolio, under normal circumstances, is expected to be more than ten years.
The Portfolio’s investments in Fixed Income Instruments are limited to those of investment grade U.S. dollar-denominated securities of U.S. issuers that are rated at least A by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”), or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In addition, the Portfolio may only invest up to 10% of its total assets in securities rated A by Moody’s, or equivalently rated by S&P or Fitch, or, if unrated, determined by PIMCO to be of comparable quality and may only invest up to 25% of its total assets in securities rated Aa by Moody’s, or equivalently rated by S&P or Fitch or, if unrated, determined by PIMCO to be of comparable quality.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Barclays Long-Term Treasury Index consists of U.S. Treasury issues with maturities of 10 or more years.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.

April 30, 2021 | PROSPECTUS  2

PIMCO Long-Term U.S. Government Portfolio

Calendar Year Total Returns — Institutional Class
Best Quarter
September 30, 2011
22.50%
Worst Quarter
December 31, 2016
-12.13%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Institutional Class Return
17.57%
7.49%
7.47%
Bloomberg Barclays Long-Term Treasury Index (reflects
no deductions for fees, expenses or taxes)
17.70%
7.85%
7.80%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Mike Cudzil and Steve Rodosky. Messrs. Cudzil and Rodosky are Managing Directors of PIMCO. Mr. Cudzil has managed the Portfolio since February 2016. Mr. Rodosky has managed the Portfolio since July 2007.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

3  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

4  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.

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PIMCO Variable Insurance Trust

Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests. These factors include the possibility that the Portfolio's commodity derivatives positions may have different roll dates, reset dates or contract months than those specified in a particular commodity index. By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.
Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.475% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.225% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Long-Term U.S. Government
Mike Cudzil
2/16
Managing Director, PIMCO. Mr. Cudzil is a portfolio manager and mortgage specialist. Prior
to joining PIMCO in 2012, he worked as a managing director and head of pass-through
trading at Nomura.
PIMCO Long-Term U.S. Government
Steve Rodosky
7/07
Managing Director, PIMCO. Mr. Rodosky joined PIMCO in 2001 and specializes in portfolio
management of treasuries, agencies and futures.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

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Prospectus

From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

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investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder

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purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.

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Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by

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the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may
participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying

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property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real
estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and

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equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
  Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a

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portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including
convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income

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Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses

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different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the
overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the

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Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions,
delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.

April 30, 2021 | PROSPECTUS  25

PIMCO Variable Insurance Trust

Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain
commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.

26  Prospectus | PIMCO Variable Insurance Trust

Prospectus

From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
The Portfolio has adopted a non-fundamental investment policy to invest at least 80% of its assets in investments suggested by its name. For purposes of this policy, the term “assets” means net assets plus the amount of any borrowings for investment purposes.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers
of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are

April 30, 2021 | PROSPECTUS  27

PIMCO Variable Insurance Trust

inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

28  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Long-Term U.S. Government Portfolio
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$12.90
$0.26
$2.02
$2.28
$(0.28)
$(0.13)
$0.00
$(0.41)
12/31/2019
11.62
0.27
1.29
1.56
(0.28)
0.00
0.00
(0.28)
12/31/2018
12.25
0.29
(0.58)
(0.29)
(0.29)
(0.05)
0.00
(0.34)
12/31/2017
11.49
0.29
0.75
1.04
(0.28)
0.00
0.00
(0.28)
12/31/2016
11.64
0.29
(0.17)
0.12
(0.27)
0.00
0.00
(0.27)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

29  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$14.77
17.57%
$50,914
0.695%
0.695%
0.475%
0.475%
1.76%
251%
12.90
13.49
39,140
0.595
0.595
0.475
0.475
2.17
129
11.62
(2.23)
39,235
0.835
0.835
0.475
0.475
2.51
164
12.25
9.12
39,545
0.615
0.615
0.475
0.475
2.42
107
11.49
0.82
36,070
0.565
0.565
0.475
0.475
2.31
135

April 30, 2021 | PROSPECTUS  30

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0596F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
SHORT DURATION BOND PORTFOLIO
PIMCO Low Duration Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Low Duration Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.50%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.69%
1
“Other Expenses” include interest expense of 0.04%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.65% for Administrative Class shares.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$70
$221
$384
$859
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 427% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 65% of its total assets in a diversified portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts, or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of this Portfolio normally varies from one to three years based on PIMCO’s forecast for interest rates. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest up to 30% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets. The Portfolio may invest up to 10% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments).
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill
its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss

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PIMCO Low Duration Portfolio

Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The ICE BofAML 1-3 Year U.S. Treasury Index is an unmanaged index comprised of U.S. Treasury securities, other than inflation-protection securities and STRIPS, with at least $1 billion in outstanding face value and a remaining term to final maturity of at least one year and less than three years.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
September 30, 2012
2.24%
Worst Quarter
June 30, 2013
-1.89%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Administrative Class Return
2.99%
2.01%
1.79%
ICE BofAML 1-3 Year U.S. Treasury Index (reflects no
deductions for fees, expenses or taxes)
3.10%
1.90%
1.30%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Scott Mather and Jerome Schneider. Mr. Mather is CIO U.S. Core Strategies and a Managing Director of PIMCO. Mr. Schneider is a Managing Director of PIMCO. Messrs. Mather and Schneider have jointly and primarily managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

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Prospectus

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction

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PIMCO Variable Insurance Trust

costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Low Duration
Scott Mather
9/14
CIO U.S. Core Strategies and Managing Director, PIMCO. Previously he was head of global
portfolio management. He joined PIMCO in 1998.
PIMCO Low Duration
Jerome Schneider
9/14
Managing Director, PIMCO. Mr. Schneider joined PIMCO in 2008. Prior to joining PIMCO, he
served as Senior Managing Director with Bear Stearns, specializing in credit and
mortgage-related funding transactions. Mr. Schneider joined Bear Stearns in 1995.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”), an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them

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or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the
Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;

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structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares.
U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary

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market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds
may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness

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of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same
underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate.

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For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be
less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”

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  Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a
portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including

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convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income
Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other

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collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the
security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future

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economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the
value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to

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withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives
strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.

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Prospectus

Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the
markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.

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PIMCO Variable Insurance Trust

ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling
a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

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Prospectus

Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

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Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Low Duration Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$10.20
$0.11
$0.19
$0.30
$(0.12)
$0.00
$0.00
$(0.12)
12/31/2019
10.08
0.28
0.12
0.40
(0.22)
0.00
(0.06)
(0.28)
12/31/2018
10.24
0.20
(0.17)
0.03
(0.19)
0.00
0.00
(0.19)
12/31/2017
10.24
0.13
0.01
0.14
(0.12)
0.00
(0.02)
(0.14)
12/31/2016
10.25
0.14
0.00
0.14
(0.07)
0.00
(0.08)
(0.15)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.38
2.99%
$1,130,716
0.69%
0.69%
0.65%
0.65%
1.04%
427%
10.20
4.03
1,007,149
1.04
1.04
0.65
0.65
2.76
308
10.08
0.34
1,197,654
0.74
0.74
0.65
0.65
1.94
624
10.24
1.35
1,272,418
0.65
0.65
0.65
0.65
1.31
544
10.24
1.41
1,248,263
0.65
0.65
0.65
0.65
1.40
391

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0340F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
SHORT DURATION BOND PORTFOLIO
PIMCO Low Duration Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Low Duration Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.50%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.79%
1
“Other Expenses” include interest expense of 0.04%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.75% for Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$81
$252
$439
$978
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 427% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 65% of its total assets in a diversified portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts, or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of this Portfolio normally varies from one to three years based on PIMCO’s forecast for interest rates. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest up to 30% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets. The Portfolio may invest up to 10% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments).
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill
its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss

April 30, 2021 | PROSPECTUS  2

PIMCO Low Duration Portfolio

Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The ICE BofAML 1-3 Year U.S. Treasury Index is an unmanaged index comprised of U.S. Treasury securities, other than inflation-protection securities and STRIPS, with at least $1 billion in outstanding face value and a remaining term to final maturity of at least one year and less than three years.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
September 30, 2012
2.21%
Worst Quarter
June 30, 2013
-1.91%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Advisor Class Return
2.89%
1.91%
1.69%
ICE BofAML 1-3 Year U.S. Treasury Index (reflects no
deductions for fees, expenses or taxes)
3.10%
1.90%
1.30%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Scott Mather and Jerome Schneider. Mr. Mather is CIO U.S. Core Strategies and a Managing Director of PIMCO. Mr. Schneider is a Managing Director of PIMCO. Messrs. Mather and Schneider have jointly and primarily managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

April 30, 2021 | PROSPECTUS  7

PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction

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PIMCO Variable Insurance Trust

costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Low Duration
Scott Mather
9/14
CIO U.S. Core Strategies and Managing Director, PIMCO. Previously he was head of global
portfolio management. He joined PIMCO in 1998.
PIMCO Low Duration
Jerome Schneider
9/14
Managing Director, PIMCO. Mr. Schneider joined PIMCO in 2008. Prior to joining PIMCO, he
served as Senior Managing Director with Bear Stearns, specializing in credit and
mortgage-related funding transactions. Mr. Schneider joined Bear Stearns in 1995.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

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From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

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circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;

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inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition,

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imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond
program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the

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volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools
because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.

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Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid
insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other

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asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or
losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy

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common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical

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service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.

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Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which
involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro

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cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates,
commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to

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the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited
to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.

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Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will
decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to

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$1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established
secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In

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such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party

34  Prospectus | PIMCO Variable Insurance Trust

Prospectus

service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

April 30, 2021 | PROSPECTUS  35

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Low Duration Portfolio
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$10.20
$0.10
$0.19
$0.29
$(0.11)
$0.00
$0.00
$(0.11)
12/31/2019
10.08
0.27
0.12
0.39
(0.21)
0.00
(0.06)
(0.27)
12/31/2018
10.24
0.19
(0.17)
0.02
(0.18)
0.00
0.00
(0.18)
12/31/2017
10.24
0.12
0.01
0.13
(0.11)
0.00
(0.02)
(0.13)
12/31/2016
10.25
0.13
0.00
0.13
(0.06)
0.00
(0.08)
(0.14)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.38
2.89%
$831,900
0.79%
0.79%
0.75%
0.75%
0.95%
427%
10.20
3.92
754,355
1.14
1.14
0.75
0.75
2.65
308
10.08
0.24
757,166
0.84
0.84
0.75
0.75
1.85
624
10.24
1.25
761,611
0.75
0.75
0.75
0.75
1.21
544
10.24
1.30
717,542
0.75
0.75
0.75
0.75
1.31
391

April 30, 2021 | PROSPECTUS  37

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1879F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
SHORT DURATION BOND PORTFOLIO
PIMCO Low Duration Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Low Duration Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.50%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.54%
1
“Other Expenses” include interest expense of 0.04%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.50% for Institutional Class shares.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$55
$173
$302
$677
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 427% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 65% of its total assets in a diversified portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts, or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of this Portfolio normally varies from one to three years based on PIMCO’s forecast for interest rates. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest up to 30% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets. The Portfolio may invest up to 10% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments).
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security. The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill
its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss

April 30, 2021 | PROSPECTUS  2

PIMCO Low Duration Portfolio

Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The ICE BofAML 1-3 Year U.S. Treasury Index is an unmanaged index comprised of U.S. Treasury securities, other than inflation-protection securities and STRIPS, with at least $1 billion in outstanding face value and a remaining term to final maturity of at least one year and less than three years.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class
Best Quarter
September 30, 2012
2.28%
Worst Quarter
June 30, 2013
-1.85%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Institutional Class Return
3.15%
2.17%
1.95%
ICE BofAML 1-3 Year U.S. Treasury Index (reflects no
deductions for fees, expenses or taxes)
3.10%
1.90%
1.30%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Scott Mather and Jerome Schneider. Mr. Mather is CIO U.S. Core Strategies and a Managing Director of PIMCO. Mr. Schneider is a Managing Director of PIMCO. Messrs. Mather and Schneider have jointly and primarily managed the Portfolio since September 2014.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction

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costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.

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Prospectus

Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Low Duration
Scott Mather
9/14
CIO U.S. Core Strategies and Managing Director, PIMCO. Previously he was head of global
portfolio management. He joined PIMCO in 1998.
PIMCO Low Duration
Jerome Schneider
9/14
Managing Director, PIMCO. Mr. Schneider joined PIMCO in 2008. Prior to joining PIMCO, he
served as Senior Managing Director with Bear Stearns, specializing in credit and
mortgage-related funding transactions. Mr. Schneider joined Bear Stearns in 1995.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

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Prospectus

From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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PIMCO Variable Insurance Trust

per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

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Prospectus

investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder

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purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.

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Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by

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the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may
participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying

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property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real
estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and

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equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign
governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.

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Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.

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Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political
subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes

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in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which
they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or

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otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant
foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but

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only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in
“Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are

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relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies
involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.

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Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled
vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a
portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of

April 30, 2021 | PROSPECTUS  33

PIMCO Variable Insurance Trust

purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches.
Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

34  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Low Duration Portfolio
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$10.20
$0.13
$0.19
$0.32
$(0.14)
$0.00
$0.00
$(0.14)
12/31/2019
10.08
0.29
0.13
0.42
(0.24)
0.00
(0.06)
(0.30)
12/31/2018
10.24
0.20
(0.15)
0.05
(0.21)
0.00
0.00
(0.21)
12/31/2017
10.24
0.15
0.00
0.15
(0.13)
0.00
(0.02)
(0.15)
12/31/2016
10.25
0.16
0.00
0.16
(0.09)
0.00
(0.08)
(0.17)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.38
3.15%
$11,436
0.54%
0.54%
0.50%
0.50%
1.21%
427%
10.20
4.18
11,474
0.89
0.89
0.50
0.50
2.86
308
10.08
0.49
8,588
0.59
0.59
0.50
0.50
2.02
624
10.24
1.50
15,368
0.50
0.50
0.50
0.50
1.44
544
10.24
1.56
8,710
0.50
0.50
0.50
0.50
1.59
391

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0599F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
REAL RETURN STRATEGY PORTFOLIO
PIMCO Real Return Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Real Return Portfolio

Investment Objective
The Portfolio seeks maximum real return, consistent with preservation of real capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.50%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.19%
Total Annual Portfolio Operating Expenses
0.84%
1
“Other Expenses” include interest expense of 0.19%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.65% for Administrative Class shares.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$86
$268
$466
$1,037
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 240% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its net assets in inflation-indexed bonds of varying maturities issued by the U.S. and non-U.S. governments, their agencies or instrumentalities and corporations, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. Assets not invested in inflation-indexed bonds may be invested in other types of Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. Inflation-indexed bonds are fixed income securities that are structured to provide protection against inflation. The value of the bond’s principal or the interest income paid on the bond is adjusted to track changes in an official inflation measure. The U.S. Treasury uses the Consumer Price Index for Urban Consumers as the inflation measure. Inflation-indexed bonds issued by a foreign government are generally adjusted to reflect a comparable inflation index, calculated by that government. “Real return” equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Effective duration, a common method of calculating duration, takes into account that for certain bonds expected cash flows will fluctuate as interest rates change and is defined in nominal yield terms, which is market convention for most bond investors and managers. Because market convention for bonds is to use nominal yields to measure effective duration, effective duration for real return bonds, which are based on real yields, are converted through a conversion factor. The resulting nominal duration typically can range from 20% and 90% of the respective real duration. All security holdings will be measured in nominal effective duration terms. Similarly, the effective duration of the Bloomberg Barclays U.S. TIPS Index will be calculated using the same conversion factors. The effective duration of this Portfolio normally varies within three years (plus or minus) of the effective duration of the securities comprising the Bloomberg Barclays U.S. TIPS Index, as calculated by PIMCO, which as of February 28, 2021 was 7.63 years.
The Portfolio invests primarily in investment grade securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”) rated B or higher by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality (except that within such 10% limitation, the Portfolio may invest in mortgage-related securities rated below B). In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio also may invest up to 30% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar denominated securities of foreign issuers. The Portfolio may invest up to 10% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation,

April 30, 2021 | PROSPECTUS  2

PIMCO Real Return Portfolio

currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Inflation-Indexed Security Risk:the risk that inflation-indexed debt securities are subject to the effects of changes in market interest rates caused by factors other than inflation (real interest rates). In general, the value of an inflation-indexed security, including TIPS, tends to decrease when real interest rates increase and can increase when real interest rates decrease. Interest payments on inflation-indexed securities are unpredictable and will fluctuate as the principal and interest are adjusted for inflation. There can be no assurance that the inflation index used will accurately measure the real rate of inflation in the prices of goods and services. Any increase in the principal amount of an inflation-indexed debt security will be considered taxable ordinary income, even though the Portfolio will not receive the principal until maturity
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Barclays U.S. TIPS Index is an unmanaged market index comprised of all U.S. Treasury Inflation-Protected Securities rated investment grade (Baa3 or better), having at least one year to final maturity, and at least $500 million par amount outstanding.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
June 30, 2020
5.29%
Worst Quarter
June 30, 2013
-8.44%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Administrative Class Return
11.71%
5.25%
3.63%
Bloomberg Barclays U.S. TIPS Index (reflects no
deductions for fees, expenses or taxes)
10.99%
5.08%
3.81%

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Steve Rodosky and Daniel He. Mr. Rodosky is a Managing Director of PIMCO, and he has managed the Portfolio since January 2019. Mr. He is an Executive Vice President of PIMCO, and he has managed the Portfolio since December 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Inflation-Indexed Security Risk
Inflation-indexed debt securities are subject to the effects of changes in market interest rates caused by factors other than inflation (real interest rates). In general, the value of an inflation-indexed security, including TIPS, tends to decrease when real interest rates increase and can increase when real interest rates decrease. Thus generally, during periods of rising inflation, the value of inflation-indexed securities will tend to increase and during periods of deflation, their value will tend to decrease. Interest payments on inflation-indexed securities are unpredictable and will fluctuate as the

April 30, 2021 | PROSPECTUS  11

PIMCO Variable Insurance Trust

principal and interest are adjusted for inflation. There can be no assurance that the inflation index used (i.e., the CPI) will accurately measure the real rate of inflation in the prices of goods and services. Increases in the principal value of TIPS due to inflation are considered taxable ordinary income for the amount of the increase in the calendar year. Any increase in the principal amount of an inflation-indexed debt security will be considered taxable ordinary income, even though the Portfolio will not receive the principal until maturity. Additionally, a CPI swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap. With municipal inflation-indexed securities, the inflation adjustment is integrated into the coupon payment, which is federally tax exempt (and may be state tax exempt). For municipal inflation-indexed securities, there is no adjustment to the principal value. Because municipal inflation-indexed securities are a small component of the municipal bond market, they may be less liquid than conventional municipal bonds.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.

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Prospectus

Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Real Return
Daniel He
12/19
Senior Vice President, PIMCO. Mr. He is a portfolio manager in the Newport Beach office. He
is a member of the liquid products group specializing in real return and mortgage-backed
securities. Prior to joining PIMCO in 2011, he structured and traded derivative strategies for
a global macro hedge fund. He previously developed trading strategies at a hedge fund that
focused on foreign exchange volatility. He has investment experience since 2005 and holds
an MBA from the University of Chicago Booth School of Business. He also holds a master's
degree in financial engineering and an undergraduate degree in computer science from the
National University of Singapore.
PIMCO Real Return
Steve Rodosky
1/19
Managing Director, PIMCO. Mr. Rodosky joined PIMCO in 2001 and specializes in portfolio
management of treasuries, agencies and futures.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the 1940 Act, an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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PIMCO Variable Insurance Trust

fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them

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or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the
Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum real return. The real return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;

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structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares.
U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary

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market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds
may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness

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of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same
underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate.

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For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be
less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”

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  Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a
portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including

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convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income
Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other

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collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the
security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future

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economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the
value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to

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withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives
strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.

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Prospectus

Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the
markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.

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ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling
a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

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Prospectus

Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

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Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Real Return Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$12.64
$0.17
$1.30
$1.47
$(0.19)
$0.00
$0.00
$(0.19)
12/31/2019
11.85
0.22
0.78
1.00
(0.21)
0.00
0.00
(0.21)
12/31/2018
12.42
0.32
(0.59)
(0.27)
(0.30)
0.00
0.00
(0.30)
12/31/2017
12.27
0.30
0.14
0.44
(0.24)
0.00
(0.05)
(0.29)
12/31/2016
11.93
0.29
0.33
0.62
(0.16)
0.00
(0.12)
(0.28)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$13.92
11.71%
$1,278,844
0.84%
0.84%
0.65%
0.65%
1.24%
240%
12.64
8.44
1,205,456
1.53
1.53
0.65
0.65
1.81
231
11.85
(2.21)
1,266,321
1.42
1.42
0.65
0.65
2.67
234
12.42
3.65
1,476,888
1.04
1.04
0.65
0.65
2.40
157
12.27
5.19
1,789,709
0.91
0.91
0.65
0.65
2.38
132

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0343F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
REAL RETURN STRATEGY PORTFOLIO
PIMCO Real Return Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Real Return Portfolio

Investment Objective
The Portfolio seeks maximum real return, consistent with preservation of real capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.50%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.19%
Total Annual Portfolio Operating Expenses
0.94%
1
“Other Expenses” include interest expense of 0.19%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.75% for Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$96
$300
$520
$1,155
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 240% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its net assets in inflation-indexed bonds of varying maturities issued by the U.S. and non-U.S. governments, their agencies or instrumentalities and corporations, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. Assets not invested in inflation-indexed bonds may be invested in other types of Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. Inflation-indexed bonds are fixed income securities that are structured to provide protection against inflation. The value of the bond’s principal or the interest income paid on the bond is adjusted to track changes in an official inflation measure. The U.S. Treasury uses the Consumer Price Index for Urban Consumers as the inflation measure. Inflation-indexed bonds issued by a foreign government are generally adjusted to reflect a comparable inflation index, calculated by that government. “Real return” equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Effective duration, a common method of calculating duration, takes into account that for certain bonds expected cash flows will fluctuate as interest rates change and is defined in nominal yield terms, which is market convention for most bond investors and managers. Because market convention for bonds is to use nominal yields to measure effective duration, effective duration for real return bonds, which are based on real yields, are converted through a conversion factor. The resulting nominal duration typically can range from 20% and 90% of the respective real duration. All security holdings will be measured in nominal effective duration terms. Similarly, the effective duration of the Bloomberg Barclays U.S. TIPS Index will be calculated using the same conversion factors. The effective duration of this Portfolio normally varies within three years (plus or minus) of the effective duration of the securities comprising the Bloomberg Barclays U.S. TIPS Index, as calculated by PIMCO, which as of February 28, 2021 was 7.63 years.
The Portfolio invests primarily in investment grade securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”) rated B or higher by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality (except that within such 10% limitation, the Portfolio may invest in mortgage-related securities rated below B). In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio also may invest up to 30% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar denominated securities of foreign issuers. The Portfolio may invest up to 10% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation,

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PIMCO Real Return Portfolio

currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Inflation-Indexed Security Risk:the risk that inflation-indexed debt securities are subject to the effects of changes in market interest rates caused by factors other than inflation (real interest rates). In general, the value of an inflation-indexed security, including TIPS, tends to decrease when real interest rates increase and can increase when real interest rates decrease. Interest payments on inflation-indexed securities are unpredictable and will fluctuate as the principal and interest are adjusted for inflation. There can be no assurance that the inflation index used will accurately measure the real rate of inflation in the prices of goods and services. Any increase in the principal amount of an inflation-indexed debt security will be considered taxable ordinary income, even though the Portfolio will not receive the principal until maturity
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Barclays U.S. TIPS Index is an unmanaged market index comprised of all U.S. Treasury Inflation-Protected Securities rated investment grade (Baa3 or better), having at least one year to final maturity, and at least $500 million par amount outstanding.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
June 30, 2020
5.27%
Worst Quarter
June 30, 2013
-8.47%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Advisor Class Return
11.60%
5.15%
3.53%
Bloomberg Barclays U.S. TIPS Index (reflects no
deductions for fees, expenses or taxes)
10.99%
5.08%
3.81%

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Steve Rodosky and Daniel He. Mr. Rodosky is a Managing Director of PIMCO, and he has managed the Portfolio since January 2019. Mr. He is an Executive Vice President of PIMCO, and he has managed the Portfolio since December 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Inflation-Indexed Security Risk
Inflation-indexed debt securities are subject to the effects of changes in market interest rates caused by factors other than inflation (real interest rates). In general, the value of an inflation-indexed security, including TIPS, tends to decrease when real interest rates increase and can increase when real interest rates decrease. Thus generally, during periods of rising inflation, the value of inflation-indexed securities will tend to increase and during periods of deflation, their value will tend to decrease. Interest payments on inflation-indexed securities are unpredictable and will fluctuate as the

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principal and interest are adjusted for inflation. There can be no assurance that the inflation index used (i.e., the CPI) will accurately measure the real rate of inflation in the prices of goods and services. Increases in the principal value of TIPS due to inflation are considered taxable ordinary income for the amount of the increase in the calendar year. Any increase in the principal amount of an inflation-indexed debt security will be considered taxable ordinary income, even though the Portfolio will not receive the principal until maturity. Additionally, a CPI swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap. With municipal inflation-indexed securities, the inflation adjustment is integrated into the coupon payment, which is federally tax exempt (and may be state tax exempt). For municipal inflation-indexed securities, there is no adjustment to the principal value. Because municipal inflation-indexed securities are a small component of the municipal bond market, they may be less liquid than conventional municipal bonds.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.

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Prospectus

Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Real Return
Daniel He
12/19
Senior Vice President, PIMCO. Mr. He is a portfolio manager in the Newport Beach office. He
is a member of the liquid products group specializing in real return and mortgage-backed
securities. Prior to joining PIMCO in 2011, he structured and traded derivative strategies for
a global macro hedge fund. He previously developed trading strategies at a hedge fund that
focused on foreign exchange volatility. He has investment experience since 2005 and holds
an MBA from the University of Chicago Booth School of Business. He also holds a master's
degree in financial engineering and an undergraduate degree in computer science from the
National University of Singapore.
PIMCO Real Return
Steve Rodosky
1/19
Managing Director, PIMCO. Mr. Rodosky joined PIMCO in 2001 and specializes in portfolio
management of treasuries, agencies and futures.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.

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The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

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From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

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Prospectus

circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum real return. The real return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;

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inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition,

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imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond
program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the

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volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools
because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.

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Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid
insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other

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asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or
losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy

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common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical

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service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.

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Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which
involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro

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cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates,
commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to

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the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited
to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.

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Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will
decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to

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$1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established
secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In

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such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party

36  Prospectus | PIMCO Variable Insurance Trust

Prospectus

service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

April 30, 2021 | PROSPECTUS  37

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Real Return Portfolio
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$12.64
$0.15
$1.31
$1.46
$(0.18)
$0.00
$0.00
$(0.18)
12/31/2019
11.85
0.21
0.77
0.98
(0.19)
0.00
0.00
(0.19)
12/31/2018
12.42
0.32
(0.60)
(0.28)
(0.29)
0.00
0.00
(0.29)
12/31/2017
12.27
0.29
0.14
0.43
(0.23)
0.00
(0.05)
(0.28)
12/31/2016
11.93
0.28
0.33
0.61
(0.15)
0.00
(0.12)
(0.27)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

38  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$13.92
11.60%
$344,989
0.94%
0.94%
0.75%
0.75%
1.09%
240%
12.64
8.33
366,402
1.63
1.63
0.75
0.75
1.70
231
11.85
(2.31)
386,746
1.52
1.52
0.75
0.75
2.60
234
12.42
3.55
520,684
1.14
1.14
0.75
0.75
2.35
157
12.27
5.09
506,438
1.01
1.01
0.75
0.75
2.31
132

April 30, 2021 | PROSPECTUS  39

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1840F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
REAL RETURN STRATEGY PORTFOLIO
PIMCO Real Return Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Real Return Portfolio

Investment Objective
The Portfolio seeks maximum real return, consistent with preservation of real capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.50%
Other Expenses(1)
0.19%
Total Annual Portfolio Operating Expenses
0.69%
1
“Other Expenses” include interest expense of 0.19%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.50% for Institutional Class shares.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$70
$221
$384
$859
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 240% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 80% of its net assets in inflation-indexed bonds of varying maturities issued by the U.S. and non-U.S. governments, their agencies or instrumentalities and corporations, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. Assets not invested in inflation-indexed bonds may be invested in other types of Fixed Income Instruments. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. Inflation-indexed bonds are fixed income securities that are structured to provide protection against inflation. The value of the bond’s principal or the interest income paid on the bond is adjusted to track changes in an official inflation measure. The U.S. Treasury uses the Consumer Price Index for Urban Consumers as the inflation measure. Inflation-indexed bonds issued by a foreign government are generally adjusted to reflect a comparable inflation index, calculated by that government. “Real return” equals total return less the estimated cost of inflation, which is typically measured by the change in an official inflation measure. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Effective duration, a common method of calculating duration, takes into account that for certain bonds expected cash flows will fluctuate as interest rates change and is defined in nominal yield terms, which is market convention for most bond investors and managers. Because market convention for bonds is to use nominal yields to measure effective duration, effective duration for real return bonds, which are based on real yields, are converted through a conversion factor. The resulting nominal duration typically can range from 20% and 90% of the respective real duration. All security holdings will be measured in nominal effective duration terms. Similarly, the effective duration of the Bloomberg Barclays U.S. TIPS Index will be calculated using the same conversion factors. The effective duration of this Portfolio normally varies within three years (plus or minus) of the effective duration of the securities comprising the Bloomberg Barclays U.S. TIPS Index, as calculated by PIMCO, which as of February 28, 2021 was 7.63 years.
The Portfolio invests primarily in investment grade securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”) rated B or higher by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality (except that within such 10% limitation, the Portfolio may invest in mortgage-related securities rated below B). In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio also may invest up to 30% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar denominated securities of foreign issuers. The Portfolio may invest up to 10% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation,

April 30, 2021 | PROSPECTUS  2

PIMCO Real Return Portfolio

currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Inflation-Indexed Security Risk:the risk that inflation-indexed debt securities are subject to the effects of changes in market interest rates caused by factors other than inflation (real interest rates). In general, the value of an inflation-indexed security, including TIPS, tends to decrease when real interest rates increase and can increase when real interest rates decrease. Interest payments on inflation-indexed securities are unpredictable and will fluctuate as the principal and interest are adjusted for inflation. There can be no assurance that the inflation index used will accurately measure the real rate of inflation in the prices of goods and services. Any increase in the principal amount of an inflation-indexed debt security will be considered taxable ordinary income, even though the Portfolio will not receive the principal until maturity
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Barclays U.S. TIPS Index is an unmanaged market index comprised of all U.S. Treasury Inflation-Protected Securities rated investment grade (Baa3 or better), having at least one year to final maturity, and at least $500 million par amount outstanding.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class
Best Quarter
June 30, 2020
5.33%
Worst Quarter
June 30, 2013
-8.41%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Institutional Class Return
11.88%
5.41%
3.78%
Bloomberg Barclays U.S. TIPS Index (reflects no
deductions for fees, expenses or taxes)
10.99%
5.08%
3.81%

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Steve Rodosky and Daniel He. Mr. Rodosky is a Managing Director of PIMCO, and he has managed the Portfolio since January 2019. Mr. He is an Executive Vice President of PIMCO, and he has managed the Portfolio since December 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Inflation-Indexed Security Risk
Inflation-indexed debt securities are subject to the effects of changes in market interest rates caused by factors other than inflation (real interest rates). In general, the value of an inflation-indexed security, including TIPS, tends to decrease when real interest rates increase and can increase when real interest rates decrease. Thus generally, during periods of rising inflation, the value of inflation-indexed securities will tend to increase and during periods of deflation, their value will tend to decrease. Interest payments on inflation-indexed securities are unpredictable and will fluctuate as the

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principal and interest are adjusted for inflation. There can be no assurance that the inflation index used (i.e., the CPI) will accurately measure the real rate of inflation in the prices of goods and services. Increases in the principal value of TIPS due to inflation are considered taxable ordinary income for the amount of the increase in the calendar year. Any increase in the principal amount of an inflation-indexed debt security will be considered taxable ordinary income, even though the Portfolio will not receive the principal until maturity. Additionally, a CPI swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap. With municipal inflation-indexed securities, the inflation adjustment is integrated into the coupon payment, which is federally tax exempt (and may be state tax exempt). For municipal inflation-indexed securities, there is no adjustment to the principal value. Because municipal inflation-indexed securities are a small component of the municipal bond market, they may be less liquid than conventional municipal bonds.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.

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Prospectus

Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.
Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Real Return
Daniel He
12/19
Senior Vice President, PIMCO. Mr. He is a portfolio manager in the Newport Beach office. He
is a member of the liquid products group specializing in real return and mortgage-backed
securities. Prior to joining PIMCO in 2011, he structured and traded derivative strategies for
a global macro hedge fund. He previously developed trading strategies at a hedge fund that
focused on foreign exchange volatility. He has investment experience since 2005 and holds
an MBA from the University of Chicago Booth School of Business. He also holds a master's
degree in financial engineering and an undergraduate degree in computer science from the
National University of Singapore.
PIMCO Real Return
Steve Rodosky
1/19
Managing Director, PIMCO. Mr. Rodosky joined PIMCO in 2001 and specializes in portfolio
management of treasuries, agencies and futures.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

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Prospectus

From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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PIMCO Variable Insurance Trust

per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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PIMCO Variable Insurance Trust

methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder

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purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum real return. The real return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.

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Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by

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the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may
participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying

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property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real
estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and

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equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign
governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.

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Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.

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Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political
subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes

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in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which
they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or

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otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant
foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but

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only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in
“Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are

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relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies
involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.

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Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled
vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a
portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of

April 30, 2021 | PROSPECTUS  33

PIMCO Variable Insurance Trust

purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches.
Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

34  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Real Return Portfolio
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$12.64
$0.19
$1.30
$1.49
$(0.21)
$0.00
$0.00
$(0.21)
12/31/2019
11.85
0.24
0.77
1.01
(0.22)
0.00
0.00
(0.22)
12/31/2018
12.42
0.34
(0.59)
(0.25)
(0.32)
0.00
0.00
(0.32)
12/31/2017
12.27
0.32
0.14
0.46
(0.26)
0.00
(0.05)
(0.31)
12/31/2016
11.93
0.30
0.34
0.64
(0.18)
0.00
(0.12)
(0.30)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$13.92
11.88%
$199,783
0.69%
0.69%
0.50%
0.50%
1.39%
240%
12.64
8.60
189,206
1.38
1.38
0.50
0.50
1.96
231
11.85
(2.06)
180,506
1.27
1.27
0.50
0.50
2.80
234
12.42
3.81
181,673
0.89
0.89
0.50
0.50
2.60
157
12.27
5.35
154,072
0.76
0.76
0.50
0.50
2.42
132

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0593F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
SHORT DURATION BOND PORTFOLIO
PIMCO Short-Term Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Short-Term Portfolio

Investment Objective
The Portfolio seeks maximum current income, consistent with preservation of capital and daily liquidity.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.45%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.02%
Total Annual Portfolio Operating Expenses
0.62%
1
“Other Expenses” include interest expense of 0.02%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.60% for Administrative Class shares.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$63
$199
$346
$774
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 114% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 65% of its total assets in a diversified portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of this Portfolio will vary based on PIMCO’s forecast for interest rates and will normally not exceed one year. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. In addition, the dollar-weighted average portfolio maturity of the Portfolio, under normal circumstances, is expected not to exceed three years.
The Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”) rated B or higher by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest up to 10% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 5% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 10% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
The Portfolio may invest all of its assets in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill
its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss

April 30, 2021 | PROSPECTUS  2

PIMCO Short-Term Portfolio

Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The FTSE 3-Month Treasury Bill Index is an unmanaged index representing monthly return equivalents of yield averages of the last 3-month Treasury Bill issues.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
June 30, 2020
3.67%
Worst Quarter
March 31, 2020
-2.22%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Administrative Class Return
2.24%
2.27%
1.70%
FTSE 3-Month Treasury Bill Index (reflects no deductions
for fees, expenses or taxes)
0.58%
1.16%
0.60%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Jerome Schneider, Andrew Wittkop and Nathan Chiaverini. Mr. Schneider is a Managing Director of PIMCO, Mr. Wittkop is an Executive Vice President of PIMCO, and Mr. Chiaverini is a Senior Vice President of PIMCO. Mr. Schneider has managed the Portfolio since January 2011, and Messrs. Wittkop and Chiaverini have managed the Portfolio since April 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

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Prospectus

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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PIMCO Variable Insurance Trust

transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.45% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.20% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Short-Term
Nathan Chiaverini
4/19
Senior Vice President, PIMCO. Mr. Chiaverini is a portfolio manager on the short-term desk.
Prior to joining PIMCO in 2012, he was a vice president and portfolio manager at BlackRock,
focusing on institutional multi-sector portfolios. Prior to this, he held trading and strategy
research positions within interest rate derivatives and mortgage-backed securities at Barclays
Capital. He has investment experience since 2004 and holds a bachelor's degree in
economics and history from the University of Colorado and an MBA in analytic finance and
economics from the University of Chicago Booth School of Business.
PIMCO Short-Term
Jerome Schneider
1/11
Managing Director, PIMCO. Mr. Schneider joined PIMCO in 2008. Prior to joining PIMCO, he
served as Senior Managing Director with Bear Stearns, specializing in credit and
mortgage-related funding transactions. Mr. Schneider joined Bear Stearns in 1995.
PIMCO Short-Term
Andrew Wittkop
4/19
Executive Vice President, PIMCO. Mr. Wittkop is a portfolio manager focusing on Treasury
bonds, agencies and interest rate derivatives. He previously worked on the real return desk.
Prior to that, he was a portfolio analyst with the global portfolio management team and a
product manager for absolute return strategies. He has investment experience since 2001
and holds an MBA from Stern School of Business at New York University and an
undergraduate degree from the University of California, Los Angeles.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”), an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders (“Market Timing Policy”). For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders. The Portfolio is not subject to the Market Timing Policy because it generally invests in more liquid, short-duration fixed income securities and PIMCO anticipates that shareholders may purchase and sell shares of the Portfolio frequently.
 The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

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circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;

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bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of
the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be

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adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease
significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an

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obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored
mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the

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current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that
are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a

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smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable

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generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets.
The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined

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by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments,
PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for

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many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign
currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.

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Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with

30  Prospectus | PIMCO Variable Insurance Trust

Prospectus

many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or
holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the

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PIMCO Variable Insurance Trust

underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment
basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.

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Prospectus

Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of
the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.

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PIMCO Variable Insurance Trust

Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Short-Term Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$10.32
$0.15
$0.08
$0.23
$(0.13)
$0.00
$0.00
$(0.13)
12/31/2019
10.29
0.27
0.01
0.28
(0.25)
0.00
0.00
(0.25)
12/31/2018
10.37
0.24
(0.08)
0.16
(0.23)
(0.01)
0.00
(0.24)
12/31/2017
10.30
0.19
0.06
0.25
(0.18)
0.00
0.00
(0.18)
12/31/2016
10.27
0.15
0.09
0.24
(0.16)
(0.05)
0.00
(0.21)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.42
2.24%
$246,924
0.62%
0.62%
0.60%
0.60%
1.40%
114%
10.32
2.80
234,168
0.79
0.79
0.60
0.60
2.62
76
10.29
1.53
233,601
0.66
0.66
0.60
0.60
2.34
71
10.37
2.40
140,075
0.75
0.75
0.60
0.60
1.88
161
10.30
2.37
136,266
0.63
0.63
0.60
0.60
1.50
862

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0339F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
SHORT DURATION BOND PORTFOLIO
PIMCO Short-Term Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Short-Term Portfolio

Investment Objective
The Portfolio seeks maximum current income, consistent with preservation of capital and daily liquidity.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.45%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.02%
Total Annual Portfolio Operating Expenses
0.72%
1
“Other Expenses” include interest expense of 0.02%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.70% for Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$74
$230
$401
$894
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 114% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 65% of its total assets in a diversified portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of this Portfolio will vary based on PIMCO’s forecast for interest rates and will normally not exceed one year. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. In addition, the dollar-weighted average portfolio maturity of the Portfolio, under normal circumstances, is expected not to exceed three years.
The Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”) rated B or higher by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest up to 10% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 5% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 10% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
The Portfolio may invest all of its assets in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill
its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss

April 30, 2021 | PROSPECTUS  2

PIMCO Short-Term Portfolio

Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The FTSE 3-Month Treasury Bill Index is an unmanaged index representing monthly return equivalents of yield averages of the last 3-month Treasury Bill issues.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
June 30, 2020
3.65%
Worst Quarter
March 31, 2020
-2.24%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Advisor Class Return
2.14%
2.16%
1.59%
FTSE 3-Month Treasury Bill Index (reflects no deductions
for fees, expenses or taxes)
0.58%
1.16%
0.60%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Jerome Schneider, Andrew Wittkop and Nathan Chiaverini. Mr. Schneider is a Managing Director of PIMCO, Mr. Wittkop is an Executive Vice President of PIMCO, and Mr. Chiaverini is a Senior Vice President of PIMCO. Mr. Schneider has managed the Portfolio since January 2011, and Messrs. Wittkop and Chiaverini have managed the Portfolio since April 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

April 30, 2021 | PROSPECTUS  7

PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

10  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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PIMCO Variable Insurance Trust

transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.45% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.20% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Short-Term
Nathan Chiaverini
4/19
Senior Vice President, PIMCO. Mr. Chiaverini is a portfolio manager on the short-term desk.
Prior to joining PIMCO in 2012, he was a vice president and portfolio manager at BlackRock,
focusing on institutional multi-sector portfolios. Prior to this, he held trading and strategy
research positions within interest rate derivatives and mortgage-backed securities at Barclays
Capital. He has investment experience since 2004 and holds a bachelor's degree in
economics and history from the University of Colorado and an MBA in analytic finance and
economics from the University of Chicago Booth School of Business.
PIMCO Short-Term
Jerome Schneider
1/11
Managing Director, PIMCO. Mr. Schneider joined PIMCO in 2008. Prior to joining PIMCO, he
served as Senior Managing Director with Bear Stearns, specializing in credit and
mortgage-related funding transactions. Mr. Schneider joined Bear Stearns in 1995.
PIMCO Short-Term
Andrew Wittkop
4/19
Executive Vice President, PIMCO. Mr. Wittkop is a portfolio manager focusing on Treasury
bonds, agencies and interest rate derivatives. He previously worked on the real return desk.
Prior to that, he was a portfolio analyst with the global portfolio management team and a
product manager for absolute return strategies. He has investment experience since 2001
and holds an MBA from Stern School of Business at New York University and an
undergraduate degree from the University of California, Los Angeles.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

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Prospectus

From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders (“Market Timing Policy”). For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders. The Portfolio is not subject to the Market Timing Policy because it generally invests in more liquid, short-duration fixed income securities and PIMCO anticipates that shareholders may purchase and sell shares of the Portfolio frequently.
 The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of

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Prospectus

the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically
valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at

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fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security
values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.

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Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on
behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;

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inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition,

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imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond
program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the

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volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools
because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.

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Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid
insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other

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asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or
losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy

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common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical

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service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.

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Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which
involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro

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cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates,
commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to

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the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited
to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.

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Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will
decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to

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$1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established
secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In

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such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party

34  Prospectus | PIMCO Variable Insurance Trust

Prospectus

service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

April 30, 2021 | PROSPECTUS  35

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Short-Term Portfolio
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$10.32
$0.14
$0.08
$0.22
$(0.12)
$0.00
$0.00
$(0.12)
12/31/2019
10.29
0.26
0.01
0.27
(0.24)
0.00
0.00
(0.24)
12/31/2018
10.37
0.23
(0.09)
0.14
(0.21)
(0.01)
0.00
(0.22)
12/31/2017
10.30
0.18
0.06
0.24
(0.17)
0.00
0.00
(0.17)
12/31/2016
10.27
0.14
0.09
0.23
(0.15)
(0.05)
0.00
(0.20)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.42
2.14%
$222,266
0.72%
0.72%
0.70%
0.70%
1.30%
114%
10.32
2.69
205,254
0.89
0.89
0.70
0.70
2.52
76
10.29
1.43
189,730
0.76
0.76
0.70
0.70
2.22
71
10.37
2.30
153,735
0.85
0.85
0.70
0.70
1.79
161
10.30
2.27
135,645
0.73
0.73
0.70
0.70
1.40
862

April 30, 2021 | PROSPECTUS  37

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1956F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
SHORT DURATION BOND PORTFOLIO
PIMCO Short-Term Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Short-Term Portfolio

Investment Objective
The Portfolio seeks maximum current income, consistent with preservation of capital and daily liquidity.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.45%
Other Expenses(1)
0.02%
Total Annual Portfolio Operating Expenses
0.47%
1
“Other Expenses” include interest expense of 0.02%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.45% for Institutional Class shares.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$48
$151
$263
$591
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 114% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 65% of its total assets in a diversified portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of this Portfolio will vary based on PIMCO’s forecast for interest rates and will normally not exceed one year. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates. In addition, the dollar-weighted average portfolio maturity of the Portfolio, under normal circumstances, is expected not to exceed three years.
The Portfolio invests primarily in investment grade debt securities, but may invest up to 10% of its total assets in high yield securities (“junk bonds”) rated B or higher by Moody’s Investors Service, Inc. (“Moody’s”), or equivalently rated by Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, determined by PIMCO to be of comparable quality. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest up to 10% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 5% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 10% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
The Portfolio may invest all of its assets in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The Portfolio may also invest up to 10% of its total assets in preferred securities.
Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill
its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss

April 30, 2021 | PROSPECTUS  2

PIMCO Short-Term Portfolio

Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The FTSE 3-Month Treasury Bill Index is an unmanaged index representing monthly return equivalents of yield averages of the last 3-month Treasury Bill issues.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class
Best Quarter
June 30, 2020
3.71%
Worst Quarter
March 31, 2020
-2.18%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Institutional Class Return
2.40%
2.42%
1.85%
FTSE 3-Month Treasury Bill Index (reflects no deductions
for fees, expenses or taxes)
0.58%
1.16%
0.60%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Jerome Schneider, Andrew Wittkop and Nathan Chiaverini. Mr. Schneider is a Managing Director of PIMCO, Mr. Wittkop is an Executive Vice President of PIMCO, and Mr. Chiaverini is a Senior Vice President of PIMCO. Mr. Schneider has managed the Portfolio since January 2011, and Messrs. Wittkop and Chiaverini have managed the Portfolio since April 2019.
Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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PIMCO Variable Insurance Trust

Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.45% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.20% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

14  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Short-Term
Nathan Chiaverini
4/19
Senior Vice President, PIMCO. Mr. Chiaverini is a portfolio manager on the short-term desk.
Prior to joining PIMCO in 2012, he was a vice president and portfolio manager at BlackRock,
focusing on institutional multi-sector portfolios. Prior to this, he held trading and strategy
research positions within interest rate derivatives and mortgage-backed securities at Barclays
Capital. He has investment experience since 2004 and holds a bachelor's degree in
economics and history from the University of Colorado and an MBA in analytic finance and
economics from the University of Chicago Booth School of Business.
PIMCO Short-Term
Jerome Schneider
1/11
Managing Director, PIMCO. Mr. Schneider joined PIMCO in 2008. Prior to joining PIMCO, he
served as Senior Managing Director with Bear Stearns, specializing in credit and
mortgage-related funding transactions. Mr. Schneider joined Bear Stearns in 1995.
PIMCO Short-Term
Andrew Wittkop
4/19
Executive Vice President, PIMCO. Mr. Wittkop is a portfolio manager focusing on Treasury
bonds, agencies and interest rate derivatives. He previously worked on the real return desk.
Prior to that, he was a portfolio analyst with the global portfolio management team and a
product manager for absolute return strategies. He has investment experience since 2001
and holds an MBA from Stern School of Business at New York University and an
undergraduate degree from the University of California, Los Angeles.
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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PIMCO Variable Insurance Trust

Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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PIMCO Variable Insurance Trust

per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders (“Market Timing Policy”). For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders. The Portfolio is not subject to the Market Timing Policy because it generally invests in more liquid, short-duration fixed income securities and PIMCO anticipates that shareholders may purchase and sell shares of the Portfolio frequently.
 The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing
sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments

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may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.

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Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks, and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.

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Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by

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the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may
participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying

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property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real
estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and

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equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign
governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.

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Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.

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Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political
subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes

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in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which
they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or

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otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant
foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but

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only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in
“Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are

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relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies
involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.

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Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled
vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a
portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of

April 30, 2021 | PROSPECTUS  33

PIMCO Variable Insurance Trust

purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches.
Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

34  Prospectus | PIMCO Variable Insurance Trust

PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Short-Term Portfolio
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$10.32
$0.17
$0.07
$0.24
$(0.14)
$0.00
$0.00
$(0.14)
12/31/2019
10.29
0.28
0.02
0.30
(0.27)
0.00
0.00
(0.27)
12/31/2018
10.37
0.26
(0.09)
0.17
(0.24)
(0.01)
0.00
(0.25)
12/31/2017
10.30
0.21
0.05
0.26
(0.19)
0.00
0.00
(0.19)
12/31/2016
10.27
0.17
0.09
0.26
(0.18)
(0.05)
0.00
(0.23)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$10.42
2.40%
$29,870
0.47%
0.47%
0.45%
0.45%
1.63%
114%
10.32
2.95
39,236
0.64
0.64
0.45
0.45
2.70
76
10.29
1.68
8,352
0.51
0.51
0.45
0.45
2.47
71
10.37
2.55
6,492
0.60
0.60
0.45
0.45
2.04
161
10.30
2.52
6,534
0.48
0.48
0.45
0.45
1.66
862

April 30, 2021 | PROSPECTUS  36

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0549F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Administrative
INTERMEDIATE DURATION BOND PORTFOLIO
PIMCO Total Return Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

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A-1


PIMCO Total Return Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Administrative Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Administrative
Class
Management Fees
0.50%
Distribution and/or Service (12b-1) Fees
0.15%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.69%
1
“Other Expenses” include interest expense of 0.04%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.65% for Administrative Class shares.
Example.The Example is intended to help you compare the cost of investing in Administrative Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Administrative Class
$70
$221
$384
$859
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 514% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 65% of its total assets in a diversified portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts, or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of this Portfolio normally varies within two years (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays U.S. Aggregate Index, as calculated by PIMCO, which as of February 28, 2021 was 6.11 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio invests primarily in investment-grade debt securities, but may invest up to 20% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest up to 30% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 15% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may invest up to 10% of its total assets in preferred securities, convertible securities and other equity-related securities. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the
underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and

April 30, 2021 | PROSPECTUS  2

PIMCO Total Return Portfolio

the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance
shown would be lower. The bar chart and the table show performance of the Portfolio’s Administrative Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable and U.S. dollar denominated. This index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Administrative Class
Best Quarter
June 30, 2020
4.23%
Worst Quarter
June 30, 2013
-3.45%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Administrative Class Return
8.65%
4.75%
3.93%
Bloomberg Barclays U.S. Aggregate Index (reflects no
deductions for fees, expenses or taxes)
7.51%
4.44%
3.84%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Scott Mather, Mark Kiesel and Mohit Mittal. Mr. Mather is CIO U.S. Core Strategies. Mr. Kiesel is CIO Global Credit. Each of Messrs. Mather, Kiesel and Mittal is a Managing Director of PIMCO. Messrs. Mather and Kiesel have jointly and primarily managed the Portfolio since September 2014, and Mr. Mittal has jointly and primarily managed the Portfolio since December 2019.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

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Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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PIMCO Variable Insurance Trust

illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

8  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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PIMCO Variable Insurance Trust

Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.
Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition

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process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Administrative Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Administrative Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Administrative Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Total Return
Mark Kiesel
9/14
CIO Global Credit and Managing Director, PIMCO. He is a member of the PIMCO Investment
Committee, a generalist portfolio manager and the global head of corporate bond portfolio
management. He has served as a portfolio manager, head of equity derivatives and as a
senior Credit Analyst since joining PIMCO in 1996.
PIMCO Total Return
Scott Mather
9/14
CIO U.S. Core Strategies and Managing Director, PIMCO. Previously he was head of global
portfolio management. He joined PIMCO in 1998.
PIMCO Total Return
Mohit Mittal
12/19
Managing Director, PIMCO. He manages Investment grade credit, total return and
unconstrained bond portfolios and is a member of the Americas Portfolio Committee.
Previously, he was a specialist on PIMCO's interest rates and derivatives desk. Mr. Mittal
joined PIMCO in 2007 and holds an MBA in finance from the Wharton School of the
University of Pennsylvania and an undergraduate degree in computer science from Indian
Institute of Technology (IIT) in Delhi, India
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Administrative Class Shares
The Trust offers investors Administrative Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Administrative Class shares.
Service Fees—Administrative Class Shares.The Trust has adopted, pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”), an Administrative Services Plan (the “Administrative Plan”) for the Administrative Class shares of the Portfolio. The Administrative Plan allows the Portfolio to use its Administrative Class assets to compensate the Distributor for providing or procuring through financial firms administrative, recordkeeping, and investor services relating to Administrative Class shares.
The Administrative Plan permits the Portfolio to make total payments at an annual rate of 0.15% of the Portfolio’s average daily net assets attributable to its Administrative Class shares. Because these fees are paid out of the Portfolio’s Administrative Class assets on an ongoing basis, over time they will increase the cost of an investment in Administrative Class shares and may cost an investor more than other types of sales charges.
Servicing Arrangements.Administrative Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Administrative Plan fees paid with respect to Administrative Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by
PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at

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conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally
scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine

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fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to
detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.

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Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities.
Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.

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Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were
sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them

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or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the
Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;

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structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares.
U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary

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market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds
may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness

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of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same
underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate.

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For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be
less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”

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  Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a
portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. The PIMCO Total Return Portfolio may not purchase common stock, but this limitation does not prevent the Portfolio from holding common stock obtained through the conversion of convertible securities or common stock that is received as part of a corporate reorganization or debt restructuring (for example, as may occur during bankruptcies or distressed situations).  Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy

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common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical

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service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.

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Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which
involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro

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cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates,
commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to

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the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited
to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.

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Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will
decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to

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$1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established
secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In

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such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party

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service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Administrative Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Total Return Portfolio
 
 
 
 
Administrative Class
 
 
 
 
 
 
 
 
12/31/2020
$11.02
$0.24
$0.70
$0.94
$(0.24)
$(0.13)
$0.00
$(0.37)
12/31/2019
10.48
0.32
0.55
0.87
(0.33)
0.00
0.00
(0.33)
12/31/2018
10.94
0.28
(0.34)
(0.06)
(0.27)
(0.13)
0.00
(0.40)
12/31/2017
10.64
0.25
0.27
0.52
(0.22)
0.00
0.00
(0.22)
12/31/2016
10.58
0.28
0.00
0.28
(0.22)
0.00
0.00
(0.22)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.59
8.65%
$3,980,729
0.69%
0.69%
0.65%
0.65%
2.08%
514%
11.02
8.36
4,031,074
0.86
0.86
0.65
0.65
2.98
534
10.48
(0.53)
3,961,602
0.91
0.91
0.65
0.65
2.62
631
10.94
4.91
4,456,274
0.69
0.69
0.65
0.65
2.28
574
10.64
2.68
4,728,701
0.66
0.66
0.65
0.65
2.56
512

April 30, 2021 | PROSPECTUS  37

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0331F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Advisor
INTERMEDIATE DURATION BOND PORTFOLIO
PIMCO Total Return Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Total Return Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Advisor Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Advisor
Class
Management Fees
0.50%
Distribution and/or Service (12b-1) Fees
0.25%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.79%
1
“Other Expenses” include interest expense of 0.04%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.75% for Advisor Class shares.
Example.The Example is intended to help you compare the cost of investing in Advisor Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Advisor Class
$81
$252
$439
$978
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 514% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 65% of its total assets in a diversified portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts, or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of this Portfolio normally varies within two years (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays U.S. Aggregate Index, as calculated by PIMCO, which as of February 28, 2021 was 6.11 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio invests primarily in investment-grade debt securities, but may invest up to 20% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest up to 30% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 15% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may invest up to 10% of its total assets in preferred securities, convertible securities and other equity-related securities. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the
underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and

April 30, 2021 | PROSPECTUS  2

PIMCO Total Return Portfolio

the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance
shown would be lower. The bar chart and the table show performance of the Portfolio’s Advisor Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable and U.S. dollar denominated. This index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Advisor Class
Best Quarter
June 30, 2020
4.20%
Worst Quarter
June 30, 2013
-3.48%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Advisor Class Return
8.54%
4.65%
3.83%
Bloomberg Barclays U.S. Aggregate Index (reflects no
deductions for fees, expenses or taxes)
7.51%
4.44%
3.84%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Scott Mather, Mark Kiesel and Mohit Mittal. Mr. Mather is CIO U.S. Core Strategies. Mr. Kiesel is CIO Global Credit. Each of Messrs. Mather, Kiesel and Mittal is a Managing Director of PIMCO. Messrs. Mather and Kiesel have jointly and primarily managed the Portfolio since September 2014, and Mr. Mittal has jointly and primarily managed the Portfolio since December 2019.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

April 30, 2021 | PROSPECTUS  5

PIMCO Variable Insurance Trust

Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

6  Prospectus | PIMCO Variable Insurance Trust

Prospectus

securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Prospectus

Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.
Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition

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Prospectus

process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Advisor Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Advisor Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Advisor Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Total Return
Mark Kiesel
9/14
CIO Global Credit and Managing Director, PIMCO. He is a member of the PIMCO Investment
Committee, a generalist portfolio manager and the global head of corporate bond portfolio
management. He has served as a portfolio manager, head of equity derivatives and as a
senior Credit Analyst since joining PIMCO in 1996.
PIMCO Total Return
Scott Mather
9/14
CIO U.S. Core Strategies and Managing Director, PIMCO. Previously he was head of global
portfolio management. He joined PIMCO in 1998.
PIMCO Total Return
Mohit Mittal
12/19
Managing Director, PIMCO. He manages Investment grade credit, total return and
unconstrained bond portfolios and is a member of the Americas Portfolio Committee.
Previously, he was a specialist on PIMCO's interest rates and derivatives desk. Mr. Mittal
joined PIMCO in 2007 and holds an MBA in finance from the Wharton School of the
University of Pennsylvania and an undergraduate degree in computer science from Indian
Institute of Technology (IIT) in Delhi, India
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Advisor Class Shares
The Trust offers investors Advisor Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Advisor Class shares.
Distribution and/or Service (12b-1) Fees – Advisor Class Shares.The Trust has adopted a Distribution and Servicing Plan for the Advisor Class shares of the Portfolio (the “Distribution and Servicing Plan”). The Distribution and Servicing Plan has been adopted pursuant to Rule 12b-1 under the Investment Company Act of 1940, as amended (the “1940 Act”). The Distribution and Servicing Plan permits the Portfolio to compensate the Distributor for providing or procuring through financial firms certain services in connection with the distribution and marketing of Advisor Class shares and/or certain shareholder services to Advisor Class shareholders.
The Distribution and Servicing Plan permits the Portfolio to make total payments at an annual rate of up to 0.25% of the Portfolio's average daily net assets attributable to its Advisor Class shares. Payments are accrued daily and paid periodically. Because these fees are paid out of the Portfolio's Advisor Class assets on an ongoing basis, over time they will increase the cost of an investment in Advisor Class shares, and Distribution and Servicing Plan fees may cost an investor more than other types of sales charges.
Servicing Arrangements.Advisor Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. The Trust pays no compensation to such entities other than Distribution and Servicing Plan fees paid with respect to Advisor Class shares. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer's investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In
addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.

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Prospectus

From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.
From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore,
also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules

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thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular

18  Prospectus | PIMCO Variable Insurance Trust

Prospectus

circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close
occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b)

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the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for
instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of

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Prospectus

these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the
Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;

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inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition,

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imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond
program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the

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volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools
because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.

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Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid
insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other

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asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.
Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or
losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. The PIMCO Total Return Portfolio may not purchase common stock, but this limitation does not prevent the Portfolio from holding common stock obtained through the conversion of convertible securities or common stock that is received as part of a corporate reorganization or debt restructuring (for example, as may occur during bankruptcies or distressed situations).  Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The

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income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial

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paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO

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will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small; differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly

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and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.
Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses

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different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws, rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the
overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the

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Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions,
delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.

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Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain
commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.

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PIMCO Variable Insurance Trust

From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents, custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party

34  Prospectus | PIMCO Variable Insurance Trust

Prospectus

service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Advisor Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Total Return Portfolio
 
 
 
 
Advisor Class
 
 
 
 
 
 
 
 
12/31/2020
$11.02
$0.23
$0.70
$0.93
$(0.23)
$(0.13)
$0.00
$(0.36)
12/31/2019
10.48
0.31
0.55
0.86
(0.32)
0.00
0.00
(0.32)
12/31/2018
10.94
0.27
(0.34)
(0.07)
(0.26)
(0.13)
0.00
(0.39)
12/31/2017
10.64
0.24
0.27
0.51
(0.21)
0.00
0.00
(0.21)
12/31/2016
10.58
0.26
0.01
0.27
(0.21)
0.00
0.00
(0.21)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

36  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.59
8.54%
$2,615,776
0.79%
0.79%
0.75%
0.75%
1.98%
514%
11.02
8.25
2,225,815
0.96
0.96
0.75
0.75
2.88
534
10.48
(0.63)
2,420,067
1.01
1.01
0.75
0.75
2.51
631
10.94
4.81
2,955,716
0.79
0.79
0.75
0.75
2.19
574
10.64
2.57
2,693,074
0.76
0.76
0.75
0.75
2.46
512

April 30, 2021 | PROSPECTUS  37

PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT1839F_043021


PIMCO Variable Insurance Trust
Prospectus
April 30, 2021
Share Class: Institutional
INTERMEDIATE DURATION BOND PORTFOLIO
PIMCO Total Return Portfolio
This prospectus is intended for use in connection with variable annuity contracts and variable life insurance policies issued by insurance companies. This prospectus should be read in conjunction with the prospectus of any contract or policy. Both prospectuses should be read carefully and retained for future reference.
As with other mutual funds, neither the U.S. Securities and Exchange Commission nor the U.S. Commodity Futures Trading Commission has approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.
As permitted by regulations adopted by the Securities and Exchange Commission, you may not be receiving paper copies of the Portfolio's shareholder reports from the insurance company that offers your contract unless you specifically request paper copies from the insurance company or from your financial intermediary Instead, the shareholder reports will be made available on a website, and the insurance company will notify you by mail each time a report is posted and provide you with a website link to access the report. Instructions for requesting paper copies will be provided by your insurance company.
If you already elected to receive shareholder reports electronically, you will not be affected by this change and you need not take any action. You may elect to receive shareholder reports and other communications from the insurance company electronically by following the instructions provided by the insurance company.
You may elect to receive all future reports in paper free of charge from the insurance company. You should contact the insurance company if you wish to continue receiving paper copies of your shareholder reports. Your election to receive reports in paper will apply to all portfolio companies available under your contract at the insurance company.

Table of Contents
 
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A-1


PIMCO Total Return Portfolio

Investment Objective
The Portfolio seeks maximum total return, consistent with preservation of capital and prudent investment management.
Fees and Expenses of the Portfolio
This table describes the fees and expenses that you may pay if you buy, hold and sell Institutional Class shares of the Portfolio. You may pay other fees, such as commissions and other fees to financial intermediaries, which are not reflected in the table and example below. Overall fees and expenses of investing in the Portfolio are higher than shown because the table does not reflect variable contract fees and expenses.
Shareholder Fees (fees paid directly from your investment):
N/A
Annual Portfolio Operating Expenses (expenses that you pay each year as a percentage of the value of your investment):
 
Institutional
Class
Management Fees
0.50%
Other Expenses(1)
0.04%
Total Annual Portfolio Operating Expenses
0.54%
1
“Other Expenses” include interest expense of 0.04%. Interest expense is borne by the Portfolio separately from the management fees paid to Pacific Investment Management Company LLC (“PIMCO”). Excluding interest expense, Total Annual Portfolio Operating Expenses are 0.50% for Institutional Class shares.
Example.The Example is intended to help you compare the cost of investing in Institutional Class shares of the Portfolio with the costs of investing in other mutual funds. The Example assumes that you invest $10,000 for the time periods indicated, and then redeem all your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Portfolio’s operating expenses remain the same. Although your actual costs may be higher or lower, the Example shows what your costs would be based on these assumptions. The Example does not reflect fees and expenses of any variable annuity contract or variable life insurance policy, and would be higher if it did.
 
1 Year
3 Years
5 Years
10 Years
Institutional Class
$55
$173
$302
$677
Portfolio Turnover
The Portfolio pays transaction costs when it buys and sells securities (or “turns over” its portfolio). A higher portfolio turnover rate may indicate higher transaction costs. These costs, which are not reflected in the Annual Portfolio Operating Expenses or in the Example table, affect the Portfolio’s performance. During the most recent fiscal year, the Portfolio’s portfolio turnover rate was 514% of the average value of its portfolio.
Principal Investment Strategies
The Portfolio seeks to achieve its investment objective by investing under normal circumstances at least 65% of its total assets in a diversified portfolio of Fixed Income Instruments of varying maturities, which may be represented by forwards or derivatives such as options, futures contracts, or swap agreements. “Fixed Income Instruments” include bonds, debt securities and other similar instruments issued by various U.S. and non-U.S. public- or private-sector entities. The average portfolio duration of this Portfolio normally varies within two years (plus or minus) of the portfolio duration of the securities comprising the Bloomberg Barclays U.S. Aggregate Index, as calculated by PIMCO, which as of February 28, 2021 was 6.11 years. Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates. The longer a security’s duration, the more sensitive it will be to changes in interest rates.
The Portfolio invests primarily in investment-grade debt securities, but may invest up to 20% of its total assets in high yield securities (“junk bonds”), as rated by Moody’s Investors Service, Inc. (“Moody’s”), Standard & Poor’s Ratings Services (“S&P”) or Fitch, Inc. (“Fitch”), or, if unrated, as determined by PIMCO. In the event that ratings services assign different ratings to the same security, PIMCO will use the highest rating as the credit rating for that security. The Portfolio may invest up to 30% of its total assets in securities denominated in foreign currencies, and may invest beyond this limit in U.S. dollar-denominated securities of foreign issuers. The Portfolio may invest up to 15% of its total assets in securities and instruments that are economically tied to emerging market countries (this limitation does not apply to investment grade sovereign debt denominated in the local currency with less than 1 year remaining to maturity, which means the Portfolio may invest, together with any other investments denominated in foreign currencies, up to 30% of its total assets in such instruments). The Portfolio will normally limit its foreign currency exposure (from non-U.S. dollar-denominated securities or currencies) to 20% of its total assets.
The Portfolio may invest, without limitation, in derivative instruments, such as options, futures contracts or swap agreements, or in mortgage- or asset-backed securities, subject to applicable law and any other restrictions described in the Portfolio’s prospectus or Statement of Additional Information. The Portfolio may purchase or sell securities on a when-issued, delayed delivery or forward commitment basis and may engage in short sales. The Portfolio may invest up to 10% of its total assets in preferred securities, convertible securities and other equity-related securities. The Portfolio may, without limitation, seek to obtain market exposure to the securities in which it primarily invests by entering into a series of purchase and sale contracts or by using other investment techniques (such as buy backs or dollar rolls). The “total return” sought by the Portfolio consists of income earned on the Portfolio’s investments, plus capital appreciation, if any, which generally arises from decreases in interest rates, foreign currency appreciation, or improving credit fundamentals for a particular sector or security.

1  PIMCO Variable Insurance Trust | Prospectus

Prospectus

Principal Risks
It is possible to lose money on an investment in the Portfolio. The principal risks of investing in the Portfolio, which could adversely affect its net asset value, yield and total return, are listed below.
Interest Rate Risk:the risk that fixed income securities will decline in value because of an increase in interest rates; a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration
Call Risk:the risk that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security that the Portfolio has invested in, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features
Credit Risk:the risk that the Portfolio could lose money if the issuer or guarantor of a fixed income security, or the counterparty to a derivative contract, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to meet its financial obligations
High Yield Risk:the risk that high yield securities and unrated securities of similar credit quality (commonly known as “junk bonds”) are subject to greater levels of credit, call and liquidity risks. High yield securities are considered primarily speculative with respect to the issuer’s continuing ability to make principal and interest payments, and may be more volatile than higher-rated securities of similar maturity
Market Risk:the risk that the value of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably, due to factors affecting securities markets generally or particular industries
Issuer Risk:the risk that the value of a security may decline for a reason directly related to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services
Liquidity Risk:the risk that a particular investment may be difficult to purchase or sell and that the Portfolio may be unable to sell illiquid investments at an advantageous time or price or achieve its desired level of exposure to a certain sector. Liquidity risk may result from the lack of an active market, reduced number and capacity of traditional market participants to make a market in fixed income securities, and may be magnified in a rising interest rate environment or other circumstances where investor redemptions from fixed income funds may be higher than normal, causing increased supply in the market due to selling activity
Derivatives Risk:the risk of investing in derivative instruments (such as futures, swaps and structured securities), including leverage, liquidity, interest rate, market, credit and management risks, and valuation complexity. Changes in the value of a derivative may not correlate perfectly with, and may be more sensitive to market events than, the
underlying asset, rate or index, and the Portfolio could lose more than the initial amount invested. The Portfolio’s use of derivatives may result in losses to the Portfolio, a reduction in the Portfolio’s returns and/or increased volatility. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse. Changes in regulation relating to a mutual fund’s use of derivatives and related instruments could potentially limit or impact the Portfolio’s ability to invest in derivatives, limit the Portfolio’s ability to employ certain strategies that use derivatives and/or adversely affect the value of derivatives and the Portfolio’s performance
Equity Risk:the risk that the value of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company or to factors affecting a particular industry or industries. Equity securities generally have greater price volatility than fixed income securities
Mortgage-Related and Other Asset-Backed Securities Risk:the risks of investing in mortgage-related and other asset-backed securities, including interest rate risk, extension risk, prepayment risk and credit risk
Foreign (Non-U.S.) Investment Risk:the risk that investing in foreign (non-U.S.) securities may result in the Portfolio experiencing more rapid and extreme changes in value than a portfolio that invests exclusively in securities of U.S. companies, due to smaller markets, differing reporting, accounting and auditing standards, increased risk of delayed settlement of portfolio transactions or loss of certificates of portfolio securities, and the risk of unfavorable foreign government actions, including nationalization, expropriation or confiscatory taxation, currency blockage, or political changes or diplomatic developments. Foreign securities may also be less liquid and more difficult to value than securities of U.S. issuers
Emerging Markets Risk:the risk of investing in emerging market securities, primarily increased foreign (non-U.S.) investment risk
Sovereign Debt Risk:the risk that investments in fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion
Currency Risk:the risk that foreign (non-U.S.) currencies will change in value relative to the U.S. dollar and affect the Portfolio’s investments in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, or in derivatives that provide exposure to, foreign (non-U.S.) currencies
Leveraging Risk:the risk that certain transactions of the Portfolio, such as reverse repurchase agreements, loans of portfolio securities, and

April 30, 2021 | PROSPECTUS  2

PIMCO Total Return Portfolio

the use of when-issued, delayed delivery or forward commitment transactions, or derivative instruments, may give rise to leverage, magnifying gains and losses and causing the Portfolio to be more volatile than if it had not been leveraged. This means that leverage entails a heightened risk of loss
Management Risk:the risk that the investment techniques and risk analyses applied by PIMCO will not produce the desired results and that actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and the individual portfolio manager in connection with managing the Portfolio and may cause PIMCO to restrict or prohibit participation in certain investments. There is no guarantee that the investment objective of the Portfolio will be achieved
Short Exposure Risk:the risk of entering into short sales, including the potential loss of more money than the actual cost of the investment, and the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio
Convertible Securities Risk:as convertible securities share both fixed income and equity characteristics, they are subject to risks to which fixed income and equity investments are subject. These risks include equity risk, interest rate risk and credit risk
LIBOR Transition Risk:the risk related to the anticipated discontinuation of the London Interbank Offered Rate (“LIBOR”). Certain instruments held by the Portfolio rely in some fashion upon LIBOR. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the nature of any replacement rate, and any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain. The transition process may involve, among other things, increased volatility or illiquidity in markets for instruments that currently rely on LIBOR and may result in a reduction in the value of certain instruments held by the Portfolio
Please see “Description of Principal Risks” in the Portfolio's prospectus for a more detailed description of the risks of investing in the Portfolio. An investment in the Portfolio is not a deposit of a bank and is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency.
Performance Information
The performance information shows summary performance information for the Portfolio in a bar chart and an Average Annual Total Returns table. The information provides some indication of the risks of investing in the Portfolio by showing changes in its performance from year to year and by showing how the Portfolio’s average annual returns compare with the returns of a broad-based securities market index. The Portfolio’s performance information reflects applicable fee waivers and/or expense limitations in effect during the periods presented. Absent such fee waivers and/or expense limitations, if any, performance would have been lower. Performance shown does not reflect any charges or expenses imposed by an insurance company, and, if it did, performance
shown would be lower. The bar chart and the table show performance of the Portfolio’s Institutional Class shares. The Portfolio’s past performance is not necessarily an indication of how the Portfolio will perform in the future.
The Bloomberg Barclays U.S. Aggregate Index represents securities that are SEC-registered, taxable and U.S. dollar denominated. This index covers the U.S. investment grade fixed rate bond market, with index components for government and corporate securities, mortgage pass-through securities, and asset-backed securities. These major sectors are subdivided into more specific indices that are calculated and reported on a regular basis.
Performance for the Portfolio is updated daily and monthly and may be obtained as follows: daily updates on the net asset value may be obtained by calling 1-888-87-PIMCO and monthly performance may be obtained at www.pimco.com/pvit.
Calendar Year Total Returns — Institutional Class
Best Quarter
June 30, 2020
4.27%
Worst Quarter
June 30, 2013
-3.41%
Average Annual Total Returns (for periods ended 12/31/20)
 
1 Year
5 Years
10 Years
Institutional Class Return
8.81%
4.91%
4.09%
Bloomberg Barclays U.S. Aggregate Index (reflects no
deductions for fees, expenses or taxes)
7.51%
4.44%
3.84%
Investment Adviser/Portfolio Manager
PIMCO serves as the investment adviser for the Portfolio. The Portfolio’s portfolio is jointly and primarily managed by Scott Mather, Mark Kiesel and Mohit Mittal. Mr. Mather is CIO U.S. Core Strategies. Mr. Kiesel is CIO Global Credit. Each of Messrs. Mather, Kiesel and Mittal is a Managing Director of PIMCO. Messrs. Mather and Kiesel have jointly and primarily managed the Portfolio since September 2014, and Mr. Mittal has jointly and primarily managed the Portfolio since December 2019.

3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Purchase and Sale of Portfolio Shares
Shares of the Portfolio currently are sold to segregated asset accounts (“Separate Accounts”) of insurance companies that fund variable annuity contracts and variable life insurance policies (“Variable Contracts”) and other funds that serve as underlying investment options for Variable Contracts (i.e., variable insurance funds). Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account.
Tax Information
The shareholders of the Portfolio are the insurance companies offering the variable products or other variable insurance funds. Please refer to the prospectus for the Separate Account and the Variable Contract for information regarding the federal income tax treatment of distributions to the Separate Account.
Payments to Insurance Companies and Other Financial Intermediaries
The Portfolio and/or its related companies (including PIMCO) may pay the insurance company and other intermediaries for the sale of the Portfolio and/or other services. These payments may create a conflict of interest by influencing the insurance company or intermediary and your salesperson to recommend a Variable Contract and the Portfolio over another investment. Ask your insurance company or salesperson or visit your financial intermediary’s Web site for more information.

April 30, 2021 | PROSPECTUS  4

Prospectus

Description of Principal Risks
The value of your investment in the Portfolio changes with the values of the Portfolio’s investments. Many factors can affect those values. The factors that are most likely to have a material effect on the Portfolio’s investments as a whole are called “principal risks.” The principal risks of the Portfolio are identified in the Portfolio Summary and are described in this section. The Portfolio may be subject to additional risks other than those identified and described below because the types of investments made by the Portfolio can change over time. Securities and investment techniques mentioned in this summary that appear in bold type are described in greater detail under “Characteristics and Risks of Securities and Investment Techniques.” That section and “Investment Objectives and Policies” in the Statement of Additional Information (“SAI”) also include more information about the Portfolio, its investments and the related risks. There is no guarantee that the Portfolio will be able to achieve its investment objective. It is possible to lose money by investing in the Portfolio.
Interest Rate Risk
Interest rate risk is the risk that fixed income securities and other instruments in the Portfolio’s portfolio will decline in value because of an increase in interest rates. As nominal interest rates rise, the value of certain fixed income securities held by the Portfolio is likely to decrease. A nominal interest rate can be described as the sum of a real interest rate and an expected inflation rate. Interest rate changes can be sudden and unpredictable, and the Portfolio may lose money as a result of movements in interest rates. The Portfolio may not be able to hedge against changes in interest rates or may choose not to do so for cost or other reasons. In addition, any hedges may not work as intended.
Fixed income securities with longer durations tend to be more sensitive to changes in interest rates, usually making them more volatile than securities with shorter durations. The values of equity and other non-fixed income securities may also decline due to fluctuations in interest rates. Inflation-indexed bonds, including Treasury Inflation-Protected Securities (“TIPS”), decline in value when real interest rates rise. In certain interest rate environments, such as when real interest rates are rising faster than nominal interest rates, inflation-indexed bonds may experience greater losses than other fixed income securities with similar durations.
Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. Inverse floating rate securities may decrease in value if interest rates increase. Inverse floating rate securities may also exhibit greater price volatility than a fixed rate obligation with similar credit quality. When the Portfolio holds variable or floating rate securities, a decrease (or, in the case of inverse floating rate securities, an increase) in market interest rates will adversely affect the income received from such securities and the net asset value (“NAV”) of the Portfolio’s shares.
A wide variety of factors can cause interest rates or yields of U.S. Treasury securities (or yields of other types of bonds) to rise (e.g., central bank monetary policies, inflation rates, general economic conditions, etc.). This is especially true under current conditions because interest rates and bond yields are near historically low levels. Thus, the Portfolio currently faces a heightened level of risk associated with rising interest rates and/or bond yields. This could be driven by a variety of factors, including but not limited to central bank monetary policies, changing inflation or real growth rates, general economic conditions, increasing bond issuances or reduced market demand for low yielding investments.
During periods of very low or negative interest rates, the Portfolio may be unable to maintain positive returns. Interest rates in the U.S. and many parts of the world, including certain European countries, are at or near historically low levels. Certain European countries have recently experienced negative interest rates on certain fixed income instruments. Very low or negative interest rates may magnify interest rate risk. Changing interest rates, including rates that fall below zero, may have unpredictable effects on markets, may result in heightened market volatility and may detract from the Portfolio’s performance to the extent the Portfolio is exposed to such interest rates.
Measures such as average duration may not accurately reflect the true interest rate sensitivity of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying durations. Therefore, if the Portfolio has an average duration that suggests a certain level of interest rate risk, the Portfolio may in fact be subject to greater interest rate risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio.
Convexity is an additional measure used to understand a security’s or the Portfolio‘s interest rate sensitivity. Convexity measures the rate of change of duration in response to changes in interest rates. With respect to a security’s price, a larger convexity (positive or negative) may imply more dramatic price changes in response to changing interest rates. Convexity may be positive or negative. Negative convexity implies that interest rate increases result in increased duration, meaning increased sensitivity in prices in response to rising interest rates. Thus, securities with negative convexity, which may include bonds with traditional call features and certain mortgage-backed securities, may experience greater losses in periods of rising interest rates. Accordingly, if the Portfolio holds such securities, the Portfolio may be subject to a greater risk of losses in periods of rising interest rates.

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Call Risk
Call risk refers to the possibility that an issuer may exercise its right to redeem a fixed income security earlier than expected (a call). Issuers may call outstanding securities prior to their maturity for a number of reasons (e.g., declining interest rates, changes in credit spreads and improvements in the issuer’s credit quality). If an issuer calls a security in which the Portfolio has invested, the Portfolio may not recoup the full amount of its initial investment and may be forced to reinvest in lower-yielding securities, securities with greater credit risks or securities with other, less favorable features.
Credit Risk
The Portfolio could lose money if the issuer or guarantor of a fixed income security (including a security purchased with securities lending collateral), or the counterparty to a derivatives contract, repurchase agreement or a loan of portfolio securities, is unable or unwilling, or is perceived (whether by market participants, rating agencies, pricing services or otherwise) as unable or unwilling, to make timely principal and/or interest payments, or to otherwise honor its obligations. The downgrade of the credit of a security held by the Portfolio may decrease its value. Securities are subject to varying degrees of credit risk, which are often reflected in credit ratings. Measures such as average credit quality may not accurately reflect the true credit risk of the Portfolio. This is especially the case if the Portfolio consists of securities with widely varying credit ratings. Therefore, if the Portfolio has an average credit rating that suggests a certain credit quality, the Portfolio may in fact be subject to greater credit risk than the average would suggest. This risk is greater to the extent the Portfolio uses leverage or derivatives in connection with the management of the Portfolio. Municipal bonds are subject to the risk that litigation, legislation or other political events, local business or economic conditions, or the bankruptcy of the issuer could have a significant effect on an issuer’s ability to make payments of principal and/or interest.
High Yield Risk
Portfolios that invest in high yield securities and unrated securities of similar credit quality (commonly known as “high yield securities” or “junk bonds”) may be subject to greater levels of credit risk, call risk and liquidity risk than portfolios that do not invest in such securities. These securities are considered predominantly speculative with respect to an issuer’s continuing ability to make principal and interest payments, and may be more volatile than other types of securities. An economic downturn or individual corporate developments could adversely affect the market for these securities and reduce the Portfolio’s ability to sell these securities at an advantageous time or price. An economic downturn would generally lead to a higher non-payment rate and, a high yield security may lose significant market value before a default occurs. High yield securities structured as zero-coupon bonds or pay-in-kind securities tend to be especially volatile as they are particularly sensitive to downward pricing pressures from rising interest rates or widening spreads and may require the Portfolio to make taxable distributions of imputed income without receiving the actual cash currency. Issuers of high yield securities may have the right to “call” or redeem the issue prior to maturity, which may result in the Portfolio having to reinvest the proceeds in other high yield securities or similar instruments that may pay lower interest rates. The Portfolio may also be subject to greater levels of liquidity risk than portfolios that do not invest in high yield securities. In addition, the high yield securities in which the Portfolio invests may not be listed on any exchange and a secondary market for such securities may be comparatively illiquid relative to markets for other more liquid fixed income securities. Consequently, transactions in high yield securities may involve greater costs than transactions in more actively traded securities. A lack of publicly-available information, irregular trading activity and wide bid/ask spreads among other factors, may, in certain circumstances, make high yield debt more difficult to sell at an advantageous time or price than other types of securities or instruments. These factors may result in the Portfolio being unable to realize full value for these securities and/or may result in the Portfolio not receiving the proceeds from a sale of a high yield security for an extended period after such sale, each of which could result in losses to the Portfolio. Because of the risks involved in investing in high yield securities, an investment in the Portfolio should be considered speculative.
Market Risk
The market price of securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Securities may decline in value due to factors affecting securities markets generally or particular industries represented in the securities markets. The value of a security may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates, adverse changes to credit markets or adverse investor sentiment generally. The value of a security may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. During a general downturn in the securities markets, multiple asset classes may decline in value simultaneously. Equity securities generally have greater price volatility than fixed income securities. Credit ratings downgrades may also negatively affect securities held by the Portfolio. Even when markets perform well, there is no assurance that the investments held by the Portfolio will increase in value along with the broader market.
In addition, market risk includes the risk that geopolitical and other events will disrupt the economy on a national or global level. For instance, war, terrorism, market manipulation, government defaults, government shutdowns, political changes or diplomatic developments, public health emergencies (such as the spread of infectious diseases, pandemics and epidemics) and natural/environmental disasters can all negatively impact the

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securities markets, which could cause the Portfolio to lose value. These events could reduce consumer demand or economic output, result in market closures, travel restrictions or quarantines, and significantly adversely impact the economy. The current contentious domestic political environment, as well as political and diplomatic events within the United States and abroad, such as presidential elections in the U.S. or abroad or the U.S. government’s inability at times to agree on a long-term budget and deficit reduction plan, has in the past resulted, and may in the future result, in a government shutdown or otherwise adversely affect the U.S. regulatory landscape, the general market environment and/or investor sentiment, which could have an adverse impact on the Portfolio’s investments and operations. Additional and/or prolonged U.S. federal government shutdowns may affect investor and consumer confidence and may adversely impact financial markets and the broader economy, perhaps suddenly and to a significant degree. Governmental and quasi-governmental authorities and regulators throughout the world have previously responded to serious economic disruptions with a variety of significant fiscal and monetary policy changes, including but not limited to, direct capital infusions into companies, new monetary programs and dramatically lower interest rates. An unexpected or sudden reversal of these policies, or the ineffectiveness of these policies, could increase volatility in securities markets, which could adversely affect the Portfolio’s investments. Any market disruptions could also prevent the Portfolio from executing advantageous investment decisions in a timely manner. To the extent that the Portfolio focuses its investments in a region enduring geopolitical market disruption, it will face higher risks of loss, although the increasing interconnectivity between global economies and financial markets can lead to events or conditions in one country, region or financial market adversely impacting a different country, region or financial market. Thus, investors should closely monitor current market conditions to determine whether the Portfolio meets their individual financial needs and tolerance for risk.
Current market conditions may pose heightened risks with respect to the Portfolio’s investment in fixed income securities. As discussed more under “Interest Rate Risk,” interest rates in the U.S. are at or near historically low levels. Any interest rate increases in the future could cause the value of the Portfolio to decrease. As such, fixed income securities markets may experience heightened levels of interest rate, volatility and liquidity risk. If rising interest rates cause the Portfolio to lose enough value, the Portfolio could also face increased shareholder redemptions, which could force the Portfolio to liquidate investments at disadvantageous times or prices, therefore adversely affecting the Portfolio and its shareholders.
Exchanges and securities markets may close early, close late or issue trading halts on specific securities or generally, which may result in, among other things, the Portfolio being unable to buy or sell certain securities or financial instruments at an advantageous time or accurately price its portfolio investments. In addition, the Portfolio may rely on various third-party sources to calculate its NAV. As a result, the Portfolio is subject to certain operational risks associated with reliance on service providers and service providers’ data sources. In particular, errors or systems failures and other technological issues may adversely impact the Portfolio’s calculation of its NAV, and such NAV calculation issues may result in inaccurately calculated NAV, delays in NAV calculation and/or the inability to calculate NAVs over extended periods. The Portfolio may be unable to recover any losses associated with such failures.
Issuer Risk
The value of a security may decline for a number of reasons that directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services, as well as the historical and prospective earnings of the issuer and the value of its assets. A change in the financial condition of a single issuer may affect securities markets as a whole.
Liquidity Risk
The Securities and Exchange Commission defines liquidity risk as the risk that the Portfolio could not meet requests to redeem shares issued by the Portfolio without significant dilution of remaining investors’ interests in the Portfolio. Liquidity risk exists when particular investments are difficult to purchase or sell. Illiquid investments are investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Illiquid investments may become harder to value, especially in changing markets. The Portfolio’s investments in illiquid investments may reduce the returns of the Portfolio because it may be unable to sell the illiquid investments at an advantageous time or price or possibly require the Portfolio to dispose of other investments at unfavorable times or prices in order to satisfy its obligations, which could prevent the Portfolio from taking advantage of other investment opportunities. Additionally, the market for certain investments may become illiquid under adverse market or economic conditions independent of any specific adverse changes in the conditions of a particular issuer. Bond markets have consistently grown over the past three decades while the capacity for traditional dealer counterparties to engage in fixed income trading has not kept pace and in some cases has decreased. As a result, dealer inventories of corporate bonds, which provide a core indication of the ability of financial intermediaries to “make markets,” are at or near historic lows in relation to market size. Because market makers seek to provide stability to a market through their intermediary services, the significant reduction in dealer inventories could potentially lead to decreased liquidity and increased volatility in the fixed income markets. Such issues may be exacerbated during periods of economic uncertainty.
In such cases, the Portfolio, due to regulatory limitations on investments in illiquid investments and the difficulty in purchasing and selling such securities or instruments, may be unable to achieve its desired level of exposure to a certain sector. To the extent that the Portfolio’s principal investment strategies involve securities of companies with smaller market capitalizations, foreign (non-U.S.) securities, Rule 144A securities,

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illiquid sectors of fixed income securities, derivatives or securities with substantial market and/or credit risk, the Portfolio will tend to have the greatest exposure to liquidity risk. Further, fixed income securities with longer durations until maturity face heightened levels of liquidity risk as compared to fixed income securities with shorter durations until maturity. Finally, liquidity risk also refers to the risk of unusually high redemption requests, redemption requests by certain large shareholders such as institutional investors or asset allocators, or other unusual market conditions that may make it difficult for the Portfolio to sell investments within the allowable time period to meet redemptions. Meeting such redemption requests could require the Portfolio to sell securities at reduced prices or under unfavorable conditions, which would reduce the value of the Portfolio. It may also be the case that other market participants may be attempting to liquidate fixed income holdings at the same time as the Portfolio, causing increased supply in the market and contributing to liquidity risk and downward pricing pressure.
Certain accounts or PIMCO affiliates may from time to time own (beneficially or of record) or control a significant percentage of the Portfolio’s shares. Redemptions by these shareholders of their holdings in the Portfolio may impact the Portfolio’s liquidity and NAV. These redemptions may also force the Portfolio to sell securities, which may negatively impact the Portfolio’s brokerage costs.
Derivatives Risk
Derivatives are financial contracts whose value depends on, or is derived from, the value of an underlying asset, reference rate or index. The various derivative instruments that the Portfolio may use are referenced under “Characteristics and Risks of Securities and Investment Techniques— Derivatives” in this prospectus and described in more detail under “Investment Objectives and Policies” in the SAI. The Portfolio typically uses derivatives as a substitute for taking a position in the underlying asset, as part of strategies designed to gain exposure to, for example, issuers, portions of the yield curve, indexes, sectors, currencies, and/or geographic regions, and/or to reduce exposure to other risks, such as interest rate, credit or currency risk. The Portfolio may also use derivatives for leverage, in which case their use would involve leveraging risk, and in some cases, may subject the Portfolio to the potential for unlimited loss. The use of derivatives may cause the Portfolio’s investment returns to be impacted by the performance of securities the Portfolio does not own and result in the Portfolio’s total investment exposure exceeding the value of its portfolio.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other traditional investments. Derivatives are subject to a number of risks described elsewhere in this section, such as liquidity risk (which may be heightened for highly-customized derivatives), interest rate risk, market risk, credit risk and management risk, as well as risks arising from changes in applicable requirements. They also involve the risk of improper valuation and the risk that changes in the value of a derivative instrument may not correlate perfectly with the underlying asset, rate or index. In this regard, the Portfolio may seek to achieve its investment objective, in part, by investing in derivatives that are designed to closely track the performance of an index on a daily basis. However, the overall investment strategies of the Portfolio are not generally designed or expected to produce returns which replicate the performance of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or the derivatives or other strategies used by the Portfolio, from achieving desired correlation with an index, such as the impact of fees, expenses and transaction costs, the timing of pricing, and disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests.  By investing in a derivative instrument, the Portfolio could lose more than the initial amount invested and derivatives may increase the volatility of the Portfolio, especially in unusual or extreme market conditions. Also, suitable derivative transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in these transactions to reduce exposure to other risks when that would be beneficial or that, if used, such strategies will be successful. In addition, the Portfolio’s use of derivatives may increase or accelerate the amount of taxes payable by shareholders. Over-the-counter (“OTC”) derivatives are also subject to the risk that a counterparty to the transaction will not fulfill its contractual obligations to the other party, as many of the protections afforded to centrally-cleared derivative transactions might not be available for OTC derivatives. The primary credit risk on derivatives that are exchange-traded or traded through a central clearing counterparty resides with the Portfolio's clearing broker or the clearinghouse.
Participation in the markets for derivative instruments involves investment risks and transaction costs to which the Portfolio may not be subject absent the use of these strategies. The skills needed to successfully execute derivative strategies may be different from those needed for other types of transactions. If the Portfolio incorrectly forecasts the value and/or creditworthiness of securities, currencies, interest rates, counterparties or other economic factors involved in a derivative transaction, the Portfolio might have been in a better position if the Portfolio had not entered into such derivative transaction. In evaluating the risks and contractual obligations associated with particular derivative instruments, it is important to consider that certain derivative transactions may be modified or terminated only by mutual consent of the Portfolio and its counterparty. Therefore, it may not be possible for the Portfolio to modify, terminate, or offset the Portfolio’s obligations or the Portfolio’s exposure to the risks associated with a derivative transaction prior to its scheduled termination or maturity date, which may create a possibility of increased volatility and/or decreased liquidity to the Portfolio. In such case, the Portfolio may lose money.

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Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, appropriate derivative transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, the Portfolio may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other appropriate counterparty can be found. When such markets are unavailable, the Portfolio will be subject to increased liquidity and investment risk.
When a derivative is used as a hedge against a position that the Portfolio holds, any loss generated by the derivative generally should be substantially offset by gains on the hedged investment, and vice versa. Although hedging can reduce or eliminate losses, it can also reduce or eliminate gains. Hedges are sometimes subject to imperfect matching between the derivative and the underlying instrument, and there can be no assurance that the Portfolio’s hedging transactions will be effective.
The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance. For instance, in October 2020, the SEC adopted a final rule related to the use of derivatives, short sales, reverse repurchase agreements and certain other transactions by registered investment companies. In connection with the final rule, the SEC and its staff will rescind and withdraw applicable guidance and relief regarding asset segregation and coverage transactions reflected in the Portfolio's asset segregation and cover practices discussed herein. Subject to certain exceptions, and after an eighteen-month transition period, the final rule requires the Portfolio to trade derivatives and other transactions that create future payment or delivery obligations (except reverse repurchase agreements and similar financing transactions) subject to value-at-risk leverage limits and certain derivatives risk management program and reporting requirements. These requirements may limit the ability of the Portfolio to invest in derivatives, short sales, reverse repurchase agreements and similar financing transactions, limit the Portfolio’s ability to employ certain strategies that use these instruments and/or adversely affect the Portfolio’s performance, efficiency in implementing its strategy, liquidity and/or ability to pursue its investment objectives and may increase the cost of the Portfolio’s investments and cost of doing business, which could adversely affect investors.
Equity Risk
Equity securities represent an ownership interest, or the right to acquire an ownership interest, in an issuer. Equity securities also include, among other things, preferred securities, convertible stocks and warrants. The values of equity securities, such as common stocks and preferred securities, may decline due to general market conditions which are not specifically related to a particular company, such as real or perceived adverse economic conditions, changes in the general outlook for corporate earnings, changes in interest or currency rates or adverse investor sentiment generally. They may also decline due to factors that affect a particular industry or industries, such as labor shortages or increased production costs and competitive conditions within an industry. Equity securities generally have greater price volatility than fixed income securities. These risks are generally magnified in the case of equity investments in distressed companies.
Mortgage-Related and Other Asset-Backed Securities Risk
Mortgage-related and other asset-backed securities represent interests in “pools” of mortgages or other assets such as consumer loans or receivables held in trust and often involve risks that are different from or possibly more acute than risks associated with other types of debt instruments. Generally, rising interest rates tend to extend the duration of fixed rate mortgage-related securities, making them more sensitive to changes in interest rates. As a result, in a period of rising interest rates, if the Portfolio holds mortgage-related securities, it may exhibit additional volatility since individual mortgage holders are less likely to exercise prepayment options, thereby putting additional downward pressure on the value of these securities and potentially causing the Portfolio to lose money. This is known as extension risk. Mortgage-backed securities can be highly sensitive to rising interest rates, such that even small movements can cause an investing Portfolio to lose value. Mortgage-backed securities, and in particular those not backed by a government guarantee, are subject to credit risk. In addition, adjustable and fixed rate mortgage-related securities are subject to prepayment risk. When interest rates decline, borrowers may pay off their mortgages sooner than expected. This can reduce the returns of the Portfolio because the Portfolio may have to reinvest that money at the lower prevailing interest rates. The Portfolio's investments in other asset-backed securities are subject to risks similar to those associated with mortgage-related securities, as well as additional risks associated with the nature of the assets and the servicing of those assets. Payment of principal and interest on asset-backed securities may be largely dependent upon the cash flows generated by the assets backing the securities, and asset-backed securities may not have the benefit of any security interest in the related assets.

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Foreign (Non-U.S.) Investment Risk
The Portfolio may invest in foreign (non-U.S.) securities and may experience more rapid and extreme changes in value than a Portfolio that invests exclusively in securities of U.S. issuers or securities that trade exclusively in U.S. markets. The securities markets of many foreign (non-U.S.) countries are relatively small, with a limited number of companies representing a small number of industries. Additionally, issuers of foreign (non-U.S.) securities are usually not subject to the same degree of regulation as U.S. issuers. Reporting, accounting and auditing standards of foreign countries differ, in some cases significantly, from U.S. standards. Global economies and financial markets are becoming increasingly interconnected, and conditions and events in one country, region or financial market may adversely impact issuers in a different country, region or financial market. Also, nationalization, expropriation or confiscatory taxation, currency blockage, market disruptions, political changes, security suspensions or diplomatic developments could adversely affect the Portfolio’s investments in a foreign country. In the event of nationalization, expropriation or other confiscation, the Portfolio could lose its entire investment in foreign (non-U.S.) securities. Adverse conditions in a certain region can adversely affect securities of other countries whose economies appear to be unrelated. To the extent that the Portfolio invests a significant portion of its assets in a specific geographic region or in securities denominated in a particular foreign (non-U.S.) currency, the Portfolio will generally have more exposure to regional economic risks, including weather emergencies and natural disasters, associated with foreign (non-U.S.) investments. Foreign (non-U.S.) securities may also be less liquid and more difficult to value than securities of U.S. issuers.
Emerging Markets Risk
Foreign (non-U.S.) investment risk may be particularly high to the extent the Portfolio invests in emerging market securities. Emerging market securities may present market, credit, currency, liquidity, legal, political, technical and other risks different from, and potentially greater than, the risks of investing in securities and instruments economically tied to developed foreign countries. To the extent the Portfolio invests in emerging market securities that are economically tied to a particular region, country or group of countries, the Portfolio may be more sensitive to adverse political or social events affecting that region, country or group of countries. Economic, business, political, or social instability may affect emerging market securities differently, and often more severely, than developed market securities. To the extent the Portfolio focuses its investments in multiple asset classes of emerging market securities it may have a limited ability to mitigate losses in an environment that is adverse to emerging market securities in general. Emerging market securities may also be more volatile, less liquid (particularly during market closures due to local market holidays or other reasons) and more difficult to value than securities economically tied to developed foreign countries. The systems and procedures for trading and settlement of securities in emerging markets are less developed and less transparent and transactions may take longer to settle. Emerging market countries typically have less established legal, accounting and financial reporting systems than those in more developed markets, which may reduce the scope or quality of financial information available to investors. Governments in emerging market countries are often less stable and more likely to take extra-legal action with respect to companies, industries, assets, or foreign ownership than those in more developed markets. Moreover, it can be more difficult for investors to bring litigation or enforce judgments against issuers in emerging markets or for U.S. regulators to bring enforcement actions against such issuers. The Portfolio may also be subject to Emerging Markets Risk if it invests in derivatives or other securities or instruments whose value or return are related to the value or returns of emerging markets securities. Rising interest rates, combined with widening credit spreads, could negatively impact the value of emerging market debt and increase funding costs for foreign issuers. In such a scenario, foreign issuers might not be able to service their debt obligations, the market for emerging market debt could suffer from reduced liquidity, and any investing Portfolio could lose money. The economy of some emerging markets may be particularly exposed to or affected by a certain industry or sector, and therefore issuers and/or securities of such emerging markets may be more affected by the performance of such industries or sectors.
Sovereign Debt Risk
Sovereign debt risk is the risk that fixed income instruments issued by sovereign entities may decline in value as a result of default or other adverse credit event resulting from an issuer’s inability or unwillingness to make principal or interest payments in a timely fashion. A sovereign entity’s failure to make timely payments on its debt can result from many factors, including, without limitation, insufficient foreign (non-U.S.) currency reserves or an inability to sufficiently manage fluctuations in relative currency valuations, an inability or unwillingness to satisfy the demands of creditors and/or relevant supranational entities regarding debt service or economic reforms, the size of the debt burden relative to economic output and tax revenues, cash flow difficulties, and other political and social considerations. The risk of loss to the Portfolio in the event of a sovereign debt default or other adverse credit event is heightened by the unlikelihood of any formal recourse or means to enforce its rights as a holder of the sovereign debt. In addition, sovereign debt restructurings, which may be shaped by entities and factors beyond the Portfolio’s control, may result in a loss in value of the Portfolio’s sovereign debt holdings.

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Currency Risk
If the Portfolio invests directly in foreign (non-U.S.) currencies or in securities that trade in, and receive revenues in, foreign (non-U.S.) currencies, or in derivatives or other instruments that provide exposure to foreign (non-U.S.) currencies, it will be subject to the risk that those currencies will decline in value relative to the U.S. dollar, or, in the case of hedging positions, that the U.S. dollar will decline in value relative to the currency being hedged.
Currency rates in foreign (non-U.S.) countries may fluctuate significantly over short periods of time for a number of reasons, including changes in interest rates, rates of inflation, balance or payments and governmental surpluses or deficits, intervention (or the failure to intervene) by U.S. or foreign (non-U.S.) governments, central banks or supranational entities such as the International Monetary Fund, or by the imposition of currency controls or other political developments in the United States or abroad. As a result, the Portfolio’s investments in foreign currency-denominated securities may reduce the returns of the Portfolio.
Currency risk may be particularly high to the extent that the Portfolio invests in foreign (non-U.S.) currencies or engages in foreign currency transactions that are economically tied to emerging market countries. These currency transactions may present market, credit, currency, liquidity, legal, political and other risks different from, or greater than, the risks of investing in developed foreign (non-U.S.) currencies or engaging in foreign currency transactions that are economically tied to developed foreign countries.
Leveraging Risk
Certain transactions may give rise to a form of leverage. Such transactions may include, among others, reverse repurchase agreements, loans of portfolio securities, and the use of when-issued, delayed delivery or forward commitment transactions. The use of derivatives may also create leveraging risk. In accordance with current federal securities laws, rules, and staff positions, PIMCO will attempt to mitigate the Portfolio’s leveraging risk by segregating or “earmarking” liquid assets or otherwise covering transactions that may give rise to such risk. The Portfolio also may be exposed to leveraging risk by borrowing money for investment purposes. Leverage may cause the Portfolio to liquidate portfolio positions to satisfy the Portfolio's obligations or to meet segregation requirements when it may not be advantageous to do so. Leverage, including borrowing, may cause the Portfolio to be more volatile than if the Portfolio had not been leveraged. This is because leverage tends to exaggerate the effect of any increase or decrease in the value of the Portfolio’s portfolio securities. Certain types of leveraging transactions, such as short sales that are not “against the box,” (i.e., short sales where the Portfolio does not hold the security or have the right to acquire it without payment of further consideration) could theoretically be subject to unlimited losses in cases where the Portfolio, for any reason, is unable to close out the transaction. In addition, to the extent the Portfolio borrows money, interest costs on such borrowings may not be recovered by any appreciation of the securities purchased with the borrowed amounts and could exceed the Portfolio’s investment returns, resulting in greater losses. Moreover, to make payments of interest and other loan costs, the Portfolio may be forced to sell portfolio securities when it is not otherwise advantageous to do so.
Management Risk
The Portfolio is subject to management risk because it is an actively managed investment portfolio. PIMCO and each individual portfolio manager will apply investment techniques and risk analysis in making investment decisions for the Portfolio, but there can be no guarantee that these decisions will produce the desired results. Certain securities or other instruments in which the Portfolio seeks to invest may not be available in the quantities desired. In addition, regulatory restrictions, actual or potential conflicts of interest or other considerations may cause PIMCO to restrict or prohibit participation in certain investments. In such circumstances, PIMCO or the individual portfolio managers may determine to purchase other securities or instruments as substitutes. Such substitute securities or instruments may not perform as intended, which could result in losses to the Portfolio. To the extent the Portfolio employs strategies targeting perceived pricing inefficiencies, arbitrage strategies or similar strategies, it is subject to the risk that the pricing or valuation of the securities and instruments involved in such strategies may change unexpectedly, which may result in reduced returns or losses to the Portfolio. The Portfolio is also subject to the risk that deficiencies in the internal systems or controls of PIMCO or another service provider will cause losses for the Portfolio or hinder Portfolio operations. For example, trading delays or errors (both human and systematic) could prevent the Portfolio from purchasing a security expected to appreciate in value. Additionally, actual or potential conflicts of interest, legislative, regulatory, or tax restrictions, policies or developments may affect the investment techniques available to PIMCO and each individual portfolio manager in connection with managing the Portfolio and may also adversely affect the ability of the Portfolio to achieve its investment objective. There also can be no assurance that all of the personnel of PIMCO will continue to be associated with PIMCO for any length of time. The loss of the services of one or more key employees of PIMCO could have an adverse impact on the Portfolio’s ability to realize its investment objective.
Short Exposure Risk
The Portfolio’s short sales, if any, are subject to special risks. A short sale involves the sale by the Portfolio of a security that it does not own with the hope of purchasing the same security at a later date at a lower price. The Portfolio may also enter into a short position through a forward commitment or a short derivative position through a futures contract or swap agreement. If the price of the security or derivative has increased during this time, then the Portfolio will incur a loss equal to the increase in price from the time that the short sale was entered into plus any

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transaction costs (i.e., premiums and interest) paid to the broker-dealer to borrow securities. Therefore, short sales involve the risk that losses may be exaggerated, potentially losing more money than the actual cost of the investment. By contrast, a loss on a long position arises from decreases in the value of the security and is limited by the fact that a security’s value cannot decrease below zero.
By investing the proceeds received from selling securities short, the Portfolio could be deemed to be employing a form of leverage, which creates special risks. The use of leverage may increase the Portfolio’s exposure to long security positions and make any change in the Portfolio’s NAV greater than it would be without the use of leverage. This could result in increased volatility of returns. There is no guarantee that any leveraging strategy the Portfolio employs will be successful during any period in which it is employed.
In times of unusual or adverse market, economic, regulatory or political conditions, the Portfolio may not be able, fully or partially, to implement its short selling strategy. Periods of unusual or adverse market, economic, regulatory or political conditions generally may exist for as long as six months and, in some cases, much longer. Also, there is the risk that the third party to the short sale will not fulfill its contractual obligations, causing a loss to the Portfolio.
Convertible Securities Risk
Convertible securities are fixed income securities, preferred securities or other securities that are convertible into or exercisable for common stock of the issuer (or cash or securities of equivalent value) at either a stated price or a stated rate. The market values of convertible securities may decline as interest rates increase and, conversely, may increase as interest rates decline. A convertible security’s market value, however, tends to reflect the market price of the common stock of the issuing company when that stock price approaches or is greater than the convertible security’s “conversion price.” The conversion price is defined as the predetermined price at which the convertible security could be exchanged for the associated stock. As the market price of the underlying common stock declines, the price of the convertible security tends to be influenced more by the yield of the convertible security. Thus, it may not decline in price to the same extent as the underlying common stock. In the event of a liquidation of the issuing company, holders of convertible securities may be paid before the company’s common stockholders but after holders of any senior debt obligations of the company. Consequently, the issuer’s convertible securities generally entail less risk than its common stock but more risk than its debt obligations.
Synthetic convertible securities involve the combination of separate securities that possess the two principal characteristics of a traditional convertible security (i.e., an income-producing component and a right to acquire an equity security). Synthetic convertible securities are often achieved, in part, through investments in warrants or options to buy common stock (or options on a stock index), and therefore are subject to the risks associated with derivatives. The value of a synthetic convertible security will respond differently to market fluctuations than a traditional convertible security because a synthetic convertible is composed of two or more separate securities or instruments, each with its own market value. Because the convertible component is typically achieved by investing in warrants or options to buy common stock at a certain exercise price, or options on a stock index, synthetic convertible securities are subject to the risks associated with derivatives. In addition, if the value of the underlying common stock or the level of the index involved in the convertible component falls below the exercise price of the warrant or option, the warrant or option may lose all value.
LIBOR Transition Risk
Certain instruments in which the Portfolio may invest rely in some fashion upon the London Interbank Offered Rate (“LIBOR”). LIBOR is an average interest rate, determined by the ICE Benchmark Administration, that banks charge one another for the use of short-term money. On July 27, 2017, the Chief Executive of the Financial Conduct Authority (“FCA”), the United Kingdom’s financial regulatory body and regulator of LIBOR, announced that after 2021 it will cease its active encouragement of banks to provide the quotations needed to sustain LIBOR due to the absence of an active market for interbank unsecured lending and other reasons. On March 5, 2021, the ICE Benchmark Administration ( “IBA”), the administrator of LIBOR, announced that it will cease publication of many of its LIBOR settings after December 31, 2021, and that it will cease publication of certain commonly-used tenors of U.S. dollar LIBOR after June 30, 2023. While the FCA may consult on the issue of requiring the IBA to produce certain LIBOR tenors on a synthetic basis, it has announced that all 35 LIBOR settings will either cease to be provided by any administrator or will no longer be representative as of the dates published by the IBA. The Board of Governors of the Federal Reserve System, Office of the Comptroller of the Currency, and Federal Deposit Insurance Corporation have issued guidance encouraging market participants to adopt alternatives to LIBOR in new contracts as soon as practicable and no later than December 31, 2021. Although the transition process away from LIBOR has become increasingly well-defined in advance of the anticipated discontinuation date, there remains uncertainty regarding the future utilization of LIBOR and the nature of any replacement rate. Any potential effects of the transition away from LIBOR on the Portfolio or on certain instruments in which the Portfolio invests can be difficult to ascertain, and they may vary depending on factors that include, but are not limited to: (i) existing fallback or termination provisions in individual contracts and (ii) whether, how, and when industry participants develop and adopt new reference rates and fallbacks for both legacy and new products and instruments. For example, certain of the Portfolio's investments may involve individual contracts that have (i) no existing fallback provision or language that contemplates the discontinuation of LIBOR or (ii) inadequate fallback provisions or language that does not contemplate a permanent discontinuation of LIBOR, and those investments could experience increased volatility or reduced liquidity as a result of the transition

12  Prospectus | PIMCO Variable Insurance Trust

Prospectus

process. In addition, interest rate provisions included in such contracts may need to be renegotiated in contemplation of the transition away from LIBOR. The transition may also result in a reduction in the value of certain instruments held by the Portfolio or a reduction in the effectiveness of related Portfolio transactions such as hedges. In addition, an instrument’s transition to a replacement rate could result in variations in the reported yields of the Portfolio that holds such instrument. Any such effects of the transition away from LIBOR, as well as other unforeseen effects, could result in losses to the Portfolio.
Disclosure of Portfolio Holdings
Please see “Disclosure of Portfolio Holdings” in the SAI for information about the availability of the complete schedule of the Portfolio’s holdings.

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Management of the Portfolio
Investment Adviser and Administrator
PIMCO serves as the investment adviser and the administrator (serving in its capacity as investment adviser, the “Investment Adviser,” and serving in its capacity as administrator, the “Administrator”) for the Portfolio. Subject to the supervision of the Board of Trustees of PIMCO Variable Insurance Trust (the “Trust”), PIMCO is responsible for managing the investment activities of the Portfolio and the Portfolio’s business affairs and other administrative matters.
PIMCO is located at 650 Newport Center Drive, Newport Beach, CA 92660. Organized in 1971, PIMCO provides investment management and advisory services to private accounts of institutional and individual clients and to mutual funds. As of December 31, 2020, PIMCO had approximately $2.21 trillion in assets under management.
Management Fees
The Portfolio pays for the advisory and supervisory and administrative services it requires under what is essentially an all-in fee structure. The Management Fees shown in the Annual Portfolio Operating Expenses table reflect both an advisory fee and a supervisory and administrative fee. For the fiscal year ended December 31, 2020, the Portfolio paid aggregate Management Fees to PIMCO at the annual rate of 0.50% (stated as a percentage of the average daily net assets of the Portfolio).
Advisory Fee.The Portfolio pays PIMCO fees in return for providing investment advisory services. For the fiscal year ended December 31, 2020, the Portfolio paid monthly advisory fees to PIMCO at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
A discussion of the basis for the Board of Trustees’ approval of the Portfolio’s investment advisory contract is available in the Portfolio’s Annual Report to shareholders for the fiscal year ended December 31, 2020.
Supervisory and Administrative Fee.The Portfolio pays for the supervisory and administrative services it requires under what is essentially an all-in fee structure. Institutional Class shareholders of the Portfolio pay a supervisory and administrative fee to PIMCO, computed as a percentage of the Portfolio’s assets attributable in the aggregate to that class of shares. PIMCO, in turn, provides or procures supervisory and administrative services for shareholders and also bears the costs of various third-party services required by the Portfolio, including audit, custodial, portfolio accounting, legal, transfer agency and printing costs. The Portfolio bears other expenses which are not covered under the supervisory and administrative fee which may vary and affect the total level of expenses paid by the Institutional Class shareholders, such as taxes and governmental fees, brokerage fees, commissions and other transaction expenses, organizational expenses, costs of borrowing money, including interest expenses, extraordinary expenses (such as litigation and indemnification expenses) and fees and expenses of the Trust’s Independent Trustees and their counsel. PIMCO generally earns a profit on the supervisory and administrative fee paid by the Portfolio. Also, under the terms of the supervision and administration agreement, PIMCO, and not Portfolio shareholders, would benefit from any price decreases in third-party services, including decreases resulting from an increase in net assets.
For the fiscal year ended December 31, 2020, the Portfolio paid PIMCO monthly supervisory and administrative fees for Institutional Class shares at the annual rate of 0.25% (stated as a percentage of the average daily net assets of the Portfolio).
Expense Limitation Agreement
PIMCO has contractually agreed, through May 1, 2022, to waive a portion of the Portfolio’s supervisory and administrative fees, or reimburse the Portfolio, to the extent that the Portfolio’s organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata share of Trustee fees exceed 0.0049% (the “Expense Limit”) (calculated as a percentage of average daily net assets attributable to each class). The Expense Limitation Agreement will automatically renew for one-year terms unless PIMCO provides written notice to the Trust at least 30 days prior to the end of the then current term. In any month in which the supervision and administration agreement is in effect, PIMCO is entitled to reimbursement by the Portfolio of any portion of the supervisory and administrative fee waived or reimbursed as set forth above (the “Reimbursement Amount”) during the previous thirty-six months from the time of the waiver, provided that such amount paid to PIMCO will not: 1) together with any organizational expenses, pro rata share of expenses related to obtaining or maintaining a Legal Entity Identifier and pro rata Trustee fees, exceed, for such month, the Expense Limit (or the amount of the expense limit in place at the time the amount being recouped was originally waived if lower than the Expense Limit); 2) exceed the total Reimbursement Amount; or 3) include any amounts previously reimbursed to PIMCO.
Individual Portfolio Managers
The following individuals have primary responsibility for managing the Portfolio.

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Prospectus

Portfolio
Portfolio Manager(s)
Since
Recent Professional Experience
PIMCO Total Return
Mark Kiesel
9/14
CIO Global Credit and Managing Director, PIMCO. He is a member of the PIMCO Investment
Committee, a generalist portfolio manager and the global head of corporate bond portfolio
management. He has served as a portfolio manager, head of equity derivatives and as a
senior Credit Analyst since joining PIMCO in 1996.
PIMCO Total Return
Scott Mather
9/14
CIO U.S. Core Strategies and Managing Director, PIMCO. Previously he was head of global
portfolio management. He joined PIMCO in 1998.
PIMCO Total Return
Mohit Mittal
12/19
Managing Director, PIMCO. He manages Investment grade credit, total return and
unconstrained bond portfolios and is a member of the Americas Portfolio Committee.
Previously, he was a specialist on PIMCO's interest rates and derivatives desk. Mr. Mittal
joined PIMCO in 2007 and holds an MBA in finance from the Wharton School of the
University of Pennsylvania and an undergraduate degree in computer science from Indian
Institute of Technology (IIT) in Delhi, India
Please see the SAI for additional information about other accounts managed by the portfolio managers, the portfolio managers’ compensation and the portfolio managers’ ownership of shares of the Portfolio.
The Trustees are responsible generally for overseeing the management of the Trust. The Trustees authorize the Trust to enter into service agreements with the Investment Adviser, the Distributor (as defined below), the Administrator and other service providers in order to provide, and in some cases authorize service providers to procure through other parties, necessary or desirable services on behalf of the Trust and the Portfolio. Shareholders are not parties to or third-party beneficiaries of such service agreements. Neither this prospectus nor summary prospectus, the Trust’s SAI, any contracts filed as exhibits to the Trust’s registration statement, nor any other communications, disclosure documents or regulatory filings from or on behalf of the Trust or the Portfolio creates a contract between or among any shareholder of the Portfolio, on the one hand, and the Trust, the Portfolio, a service provider to the Trust or the Portfolio, and/or the Trustees or officers of the Trust, on the other hand. The Trustees (or the Trust and its officers, service providers or other delegates acting under authority of the Trustees) may amend this, or use a new prospectus, summary prospectus or SAI with respect to the Portfolio or the Trust, and/or amend, file and/or issue any other communications, disclosure documents or regulatory filings, and may amend or enter into any contracts to which the Trust or the Portfolio is a party, and interpret the investment objective(s), policies, restrictions and contractual provisions applicable to the Portfolio, without shareholder input or approval, except in circumstances in which shareholder approval is specifically required by law (such as changes to fundamental investment policies) or where a shareholder approval requirement is specifically disclosed in the Trust’s then-current prospectus or SAI.
Distributor
The Trust’s Distributor is PIMCO Investments LLC (the “Distributor”). The Distributor, located at 1633 Broadway, New York, NY 10019, is a broker-dealer registered with the Securities and Exchange Commission (“SEC”).

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Institutional Class Shares
The Trust offers investors Institutional Class shares of the Portfolio in this prospectus. The Trust does not charge any sales charges (loads) or other fees in connection with purchases or redemptions of Institutional Class shares.
Servicing Arrangements.Institutional Class shares of the Portfolio may be offered through certain brokers and financial intermediaries (“servicers”) that have established a shareholder servicing relationship with the Trust on behalf of their customers. Servicers may impose additional or different conditions than the Trust on purchases, redemptions or exchanges of Portfolio shares by their customers. Servicers may also independently establish and charge their customers transaction fees, account fees and other amounts in connection with purchases and redemptions of Portfolio shares in addition to any fees charged by the Trust. These additional fees may vary over time and would increase the cost of the customer’s investment and lower investment returns. Each servicer is responsible for transmitting to its customers a schedule of any such fees and information regarding any additional or different conditions regarding purchases, redemptions and exchanges. Shareholders who are customers of servicers should consult their servicers for information regarding these fees and conditions.
Additional Payments.PIMCO uses its own assets and resources, including its profits from advisory or supervisory and administrative fees paid by the Portfolio, to pay insurance companies for services rendered to current and prospective owners of Variable Contracts, including the provision of support services such as providing information about the Trust and the Portfolio, the delivery of Trust documents, and other services. In addition, PIMCO may pay certain expenses, such as printing and mailing charges, incurred by such insurance companies in connection with their services. Any such payments are made by PIMCO, and not by the Trust, and PIMCO does not receive any separate fees for such expenses.
The fees paid to insurance companies, as described in the preceding paragraph, generally will not exceed 0.25% of the total assets of the Portfolio held by the insurance company, on an annual basis, though in some cases, may be up to 0.35%. Although the payments described in the preceding paragraph are not intended to compensate the insurance companies for marketing the Portfolio, they may provide an additional incentive to insurance companies to actively promote the Portfolio and, depending on the arrangements an insurance company may have in place with other mutual funds or their sponsors at any particular time, an insurance company may have a financial incentive to promote the Portfolio (or share class of the Portfolio) over other mutual fund options (or other Portfolios or share classes of the Portfolio) available under a particular Variable Contract.
In addition, the Distributor, PIMCO and their affiliates may from time to time make payments and provide other incentives to insurance companies as compensation for services such as providing the Portfolio with a higher profile for the insurance companies’ financial advisors and
their customers or otherwise identifying the Portfolio as being part of a complex to be accorded a higher degree of marketing support than complexes not making such payments, granting the Distributor access to the insurance companies’ financial advisors (including through the insurance companies’ intranet websites) in order to promote the Portfolio, promotions in communications with current and prospective Variable Contract owners such as in the insurance companies’ internet websites or in customer newsletters, providing assistance in training and educating the insurance companies’ personnel, and furnishing marketing support and other specified services. The actual services provided, and the payments made for such services, vary from company to company. These payments may be significant to the insurance companies.
A number of factors will be considered in determining the amount of these additional payments to insurance companies. The Distributor, PIMCO and their affiliates may make payments to one or more insurance companies based upon factors such as the amount of assets an insurance company’s accounts have invested in the Portfolio and the quality of the insurance company’s relationship with the Distributor, PIMCO and their affiliates.
The additional payments described above are made from the Distributor’s or PIMCO’s (or their affiliates’) own assets (and sometimes, therefore referred to as “revenue sharing”) pursuant to agreements with insurance companies or other financial firms and do not change the price paid by an insurance company’s separate account for the purchase of the Portfolio’s shares or the amount the Portfolio will receive as proceeds from such sales. These payments may be made to insurance companies (as selected by the Distributor) that have invested significant amounts in shares of the Portfolio. The level of payments made to a financial firm in any future year will vary.
From time to time, PIMCO, and/or the Distributor may pay or reimburse insurance companies, broker-dealers, banks, recordkeepers or other financial institutions for PIMCO’s and/or the Distributor’s attendance at conferences, seminars or informational meetings sponsored by such firms, or PIMCO and/or the Distributor may co-sponsor such events with such financial institutions. PIMCO and/or the Distributor may also provide other non-cash compensation in the form of reimbursement for reasonable travel and lodging expenses for attendees of PIMCO educational events, occasional meals, tickets or other entertainment, as well as small gifts to such firms’ representatives and charitable contributions to valid charitable organizations, as permitted by applicable law, rules and regulations. Payments and reimbursements for such activities are made out of PIMCO’s and/or the Distributor’s own assets and at no cost to the Portfolio. These payments and reimbursements may be made from profits received by PIMCO from advisory fees and supervisory and administrative fees paid to PIMCO by the Portfolio. Such activities by PIMCO and/or the Distributor may provide incentives to financial institutions to sell shares of the Portfolio. Additionally, these activities may give PIMCO and/or the Distributor additional access to sales representatives of such financial institutions, which may increase sales of Portfolio shares.

16  Prospectus | PIMCO Variable Insurance Trust

Prospectus

From time to time, PIMCO, the Distributor or their affiliates may pay investment consultants or their parent or affiliated companies for certain services including technology, operations, tax, or audit consulting services, and may pay such firms for the Distributor’s or PIMCO’s attendance at investment forums sponsored by such firms or for various studies, surveys, industry data, access to databases, research and information about, and contact information for, particular sales representatives who have sold, or may in the future sell, Portfolio shares (i.e., “data”). Subject to applicable law, PIMCO and its affiliates may also provide investment advisory services to investment consultants and their affiliates and may execute brokerage transactions on behalf of the Portfolio with such investment consultants and their affiliates. These consultants or their affiliates may, in the ordinary course of their investment consultant business, recommend that their clients utilize PIMCO’s investment advisory services or invest in the Portfolio or in other products sponsored by PIMCO, the Distributor, and their affiliates.
The SAI contains further details about the payments made by PIMCO and/or the Distributor to insurance companies. In addition, you can ask the insurance company that sponsors the Variable Contract in which you invest for information about any payments it receives from PIMCO and/or the Distributor and any services provided for such payments.
Purchases and Redemptions
Investors do not deal directly with the Portfolio to purchase and redeem shares. Please refer to the prospectus for the Separate Account for information on the allocation of premiums and on transfers of accumulated value among sub-accounts of the Separate Account that invest in the Portfolio.
On any day that regular trading on the New York Stock Exchange (“NYSE”) closes earlier than scheduled, the Portfolio reserves the right to: (i) advance the time as of which the NAV is calculated and, therefore, also the time by which purchase and redemption orders must be received in order to receive that day’s NAV or (ii) accept purchase and redemption orders until, and calculate its NAV as of, the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not accept purchase and redemption orders (or calculate its NAV) on days that the NYSE is closed for business (scheduled or unscheduled). However, on any day that the NYSE is closed when it would normally be open for business, the Portfolio may accept purchase and redemption orders until (and calculate its NAV as of) the normally scheduled close of regular trading on the NYSE or such other time that the Portfolio may determine.
Purchasing Shares
As of the date of this prospectus, shares of the Portfolio are offered for purchase either directly or indirectly (i.e., through other variable insurance funds) by Separate Accounts to serve as an investment medium for Variable Contracts issued by life insurance companies. All purchase orders are effected at the NAV next determined after a purchase order is received.
While the Portfolio currently does not foresee any disadvantages to Variable Contract Owners if the Portfolio serves as an investment medium for both variable annuity contracts and variable life insurance policies, due to differences in tax treatment or other considerations, it is theoretically possible that the interest of owners of annuity contracts and insurance policies for which the Portfolio serves as an investment medium might at some time be in conflict. However, the Trust’s Board of Trustees and each insurance company with a separate account allocating assets to the Portfolio are required to monitor events to identify any material conflicts between variable annuity contract owners and variable life insurance policy owners, and would have to determine what action, if any, should be taken in the event of such a conflict. If such a conflict occurred, an insurance company participating in the Portfolio might be required to redeem the investment of one or more of its separate accounts from the Portfolio, which might force the Portfolio to sell securities at disadvantageous prices.
The Trust and its Distributor each reserves the right, in its sole discretion, to suspend the offering of shares of the Portfolio or to reject any purchase order, in whole or in part, when, in the judgment of management, such suspension or rejection is in the best interests of the Trust. In addition, the Trust and its Distributor each reserves the right, in its sole discretion, to redeem shares, in whole or in part, when, in the judgment of management, such redemption is necessary in order to maintain qualification under the rules for variable annuities and/or variable life contracts with respect to other shareholders, to maintain qualification as a regulated investment company under the Internal Revenue Code of 1986, as amended (the “Code”), or for any reason under terms set by the Trustees, including the failure of a shareholder to supply a personal identification number if required to do so, or to have the minimum investment required, or to pay when due for the purchase of shares issued to the shareholder. The exercise of the Trust's and the Distributor's right to redeem shares in the foregoing circumstances is subject to any applicable provisions of the 1940 Act and the rules thereunder. The offering of shares will be suspended when trading on the NYSE is restricted or during an emergency which makes it impracticable for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. In the event that the Portfolio ceases offering its shares, any investments allocated to the Portfolio will, subject to any necessary regulatory approvals, be invested in another Portfolio of the Trust.
The Trust generally does not offer or sell its shares outside of the United States, except to certain investors in approved jurisdictions and in conformity with local legal requirements.
Redeeming Shares
Shares may be redeemed without charge on any day that the NAV is calculated. Under normal circumstances, all redemption requests received by the Trust or its designee prior to the close of regular trading on the NYSE (normally 4:00 pm, Eastern time (“NYSE Close”)), on a day the Trust is open for business, are effective on that day. Redemption requests received after that time become effective on the next business day. Redemption requests for Portfolio shares are effected at the NAV

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per share next determined after receipt of a redemption request by the Trust or its designee. Payment for shares redeemed normally will be made within seven days.
Redemptions of Portfolio shares may be suspended when trading on the NYSE is restricted or during an emergency which makes it impractical for the Portfolio to dispose of its securities or to determine fairly the value of its net assets, or during any other period as permitted by the SEC for the protection of investors. Under these and other unusual circumstances, the Trust may suspend redemption or postpone payment for more than seven days, as permitted by law. In consideration of the best interests of the remaining shareholders, the Trust reserves the right to pay redemption proceeds in whole or in part by a distribution in kind of securities held by the Portfolio in lieu of cash. It is highly unlikely that shares would ever be redeemed in kind. If shares are redeemed in kind, however, the redeeming shareholder should expect to incur transaction costs upon the disposition of the securities received in the distribution.
In order to meet redemption requests, the Portfolio typically expects to use a combination of sales of portfolio assets, holdings of cash and cash equivalents (including cash flows into the Portfolio) and financing transactions (such as reverse repurchase agreements). These methods of meeting redemption requests are expected to be used regularly. The Portfolio reserves the right to use other types of borrowings and interfund lending. The use of borrowings (such as a line of credit) and interfund lending in order to meet redemption requests is typically expected to be used only during stressed market conditions, if at all. See “Characteristics and Risks of Securities and Investment Techniques—Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings” and the SAI for more information. The Portfolio's use of redemptions in kind is discussed above.
Frequent or Excessive Purchases, Exchanges and Redemptions
The Trust encourages shareholders to invest in the Portfolio as part of a long-term investment strategy and discourages excessive, short-term trading and other abusive trading practices, sometimes referred to as “market timing.” However, because the Trust will not always be able to detect market timing or other abusive trading activity, investors should not assume that the Trust will be able to detect or prevent all market timing or other trading practices that may disadvantage the Portfolio.
Certain of the Portfolio’s investment strategies may expose the Portfolio to risks associated with market timing activities. For example, since the Portfolio may invest in non-U.S. securities, it may be subject to the risk that an investor may seek to take advantage of a delay between the change in value of the Portfolio’s non-U.S. portfolio securities and the determination of the Portfolio’s NAV as a result of different closing times of U.S. and non-U.S. markets by buying or selling Portfolio shares at a price that does not reflect their true value. A similar risk exists for the Portfolio’s potential investment in securities of small capitalization companies, securities of issuers located in emerging markets, securities of distressed companies or high yield securities that are thinly traded and therefore may have actual values that differ from their market prices.
To discourage excessive, short-term trading and other abusive trading practices, the Board of Trustees of the Trust has adopted policies and procedures reasonably designed to detect and prevent short-term trading activity that may be harmful to the Portfolio and its shareholders. Such activities may have a detrimental effect on the Portfolio and its shareholders. For example, depending upon various factors such as the size of the Portfolio and the amount of its assets maintained in cash, short-term or excessive trading by Portfolio shareholders may interfere with the efficient management of the Portfolio’s investments, increase transaction costs and taxes, and may harm the performance of the Portfolio and its shareholders.
The Trust seeks to deter and prevent abusive trading practices, and to reduce these risks, through several methods. First, to the extent that there is a delay between a change in the value of the Portfolio’s holdings, and the time when that change is reflected in the NAV of the Portfolio’s shares, the Portfolio is exposed to the risk that investors may seek to exploit this delay by purchasing or redeeming shares at NAVs that do not reflect appropriate fair value prices. The Trust seeks to deter and prevent this activity, sometimes referred to as “stale price arbitrage,” by the appropriate use of “fair value” pricing of the Portfolio’s securities. See “How Portfolio Shares Are Priced” below for more information.
Second, the Trust and PIMCO seek to monitor shareholder account activities in order to detect and prevent excessive and disruptive trading practices. The Trust and PIMCO each reserves the right to restrict or refuse any purchase or exchange transactions if, in the judgment of the Trust or of PIMCO, the transaction may adversely affect the interests of the Portfolio or its shareholders. Among other things, the Trust may monitor for any patterns of frequent purchases and sales that appear to be made in response to short-term fluctuations in share price. Notice of such restrictions, if any, will vary according to the particular circumstances. When PIMCO notices a pattern of trading that may be indicative of excessive or abusive trading by Variable Contract Owners, the Trust and/or PIMCO will seek the cooperation of insurance companies.
Although the Trust and its service providers seek to use these methods to detect and prevent abusive trading activities, and although the Trust will consistently apply such methods, there can be no assurances that such activities can be mitigated or eliminated. By their nature, insurance company separate accounts, in which purchases and redemptions of Portfolio shares by Variable Contract Owners are aggregated for presentation to the Portfolio on a net basis, conceal the identity of the individual Variable Contract Owners from the Portfolio. This makes it more difficult for the Trust and/or PIMCO to identify short-term transactions in the Portfolio.
How Portfolio Shares are Priced
The price of the Portfolio’s shares is based on the Portfolio’s NAV. The NAV of the Portfolio, or each of its share classes, as applicable, is determined by dividing the total value of the Portfolio’s portfolio

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investments and other assets attributable to that Portfolio or class, less any liabilities, by the total number of shares outstanding of that Portfolio or class.
On each day that the NYSE is open, Portfolio shares are ordinarily valued as of the NYSE Close. Information that becomes known to the Portfolio or its agents after the time as of which NAV has been calculated on a particular day will not generally be used to retroactively adjust the price of a security or the NAV determined earlier that day. If regular trading on the NYSE closes earlier than scheduled, the Portfolio reserves the right to either (i) calculate its NAV as of the earlier closing time or (ii) calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day. The Portfolio generally does not calculate its NAV on days during which the NYSE is closed. However, if the NYSE is closed on a day it would normally be open for business, the Portfolio reserves the right to calculate its NAV as of the normally scheduled close of regular trading on the NYSE for that day or such other time that the Portfolio may determine.
For purposes of calculating NAV, portfolio securities and other assets for which market quotes are readily available are valued at market value. Market value is generally determined on the basis of official closing prices or the last reported sales prices, or if no sales are reported, based on quotes obtained from established market makers or prices (including evaluated prices) supplied by the Portfolio’s approved pricing services, quotation reporting systems and other third-party sources (together, “Pricing Services”). The Portfolio will normally use pricing data for domestic equity securities received shortly after the NYSE Close and does not normally take into account trading, clearances or settlements that take place after the NYSE Close. A foreign (non-U.S.) equity security traded on a foreign exchange or on more than one exchange is typically valued using pricing information from the exchange considered by PIMCO to be the primary exchange. If market value pricing is used, a foreign (non-U.S.) equity security will be valued as of the close of trading on the foreign exchange, or the NYSE Close, if the NYSE Close occurs before the end of trading on the foreign exchange. Domestic and foreign (non-U.S.) fixed income securities, non-exchange traded derivatives, and equity options are normally valued on the basis of quotes obtained from brokers and dealers or Pricing Services using data reflecting the earlier closing of the principal markets for those securities. Prices obtained from Pricing Services may be based on, among other things, information provided by market makers or estimates of market values obtained from yield data relating to investments or securities with similar characteristics. Certain fixed income securities purchased on a delayed-delivery basis are marked to market daily until settlement at the forward settlement date. Exchange-traded options, except equity options, futures and options on futures are valued at the settlement price determined by the relevant exchange. Swap agreements are valued on the basis of bid quotes obtained from brokers and dealers or market-based prices supplied by Pricing Services or other pricing sources. With respect to any portion of the Portfolio’s assets that are invested in one or more open-end management investment companies (other than exchange-traded funds (“ETFs”)), the Portfolio’s NAV will be calculated based on the NAVs of such investments.
If a foreign (non-U.S.) equity security’s value has materially changed after the close of the security’s primary exchange or principal market but before the NYSE Close, the security may be valued at fair value based on procedures established and approved by the Board of Trustees (the “Board”). Foreign (non-U.S.) equity securities that do not trade when the NYSE is open are also valued at fair value. With respect to foreign (non-U.S.) equity securities, the Portfolio may determine the fair value of investments based on information provided by Pricing Services and other third-party vendors, which may recommend fair value or adjustments with reference to other securities, indexes or assets. In considering whether fair valuation is required and in determining fair values, the Portfolio may, among other things, consider significant events (which may be considered to include changes in the value of U.S. securities or securities indexes) that occur after the close of the relevant market and before the NYSE Close. The Portfolio may utilize modeling tools provided by third-party vendors to determine fair values of non-U.S. securities. For these purposes, any movement in the applicable reference index or instrument (“zero trigger”) between the earlier close of the applicable foreign market and the NYSE Close may be deemed to be a significant event, prompting the application of the pricing model (effectively resulting in daily fair valuations). Foreign (non-U.S.) exchanges may permit trading in foreign (non-U.S.) equity securities on days when the Trust is not open for business, which may result in the Portfolio’s portfolio investments being affected when you are unable to buy or sell shares.
Senior secured floating rate loans for which an active secondary market exists to a reliable degree will be valued at the mean of the last available bid/ask prices in the market for such loans, as provided by a Pricing Service. Senior secured floating rate loans for which an active secondary market does not exist to a reliable degree will be valued at fair value, which is intended to approximate market value. In valuing a senior secured floating rate loan at fair value, the factors considered may include, but are not limited to, the following: (a) the creditworthiness of the borrower and any intermediate participants, (b) the terms of the loan, (c) recent prices in the market for similar loans, if any, and (d) recent prices in the market for instruments of similar quality, rate, period until next interest rate reset and maturity.
Investments valued in currencies other than the U.S. dollar are converted to the U.S. dollar using exchange rates obtained from Pricing Services. As a result, the value of such investments and, in turn, the NAV of the Portfolio’s shares may be affected by changes in the value of currencies in relation to the U.S. dollar. The value of investments traded in markets outside the United States or denominated in currencies other than the U.S. dollar may be affected significantly on a day that the Trust is not open for business. As a result, to the extent that the Portfolio holds foreign (non-U.S.) investments, the value of those investments may change at times when shareholders are unable to buy or sell shares and the value of such investments will be reflected in the Portfolio’s next calculated NAV.
Investments for which market quotes or market based valuations are not readily available are valued at fair value as determined in good faith by the Board or persons acting at their direction. The Board has adopted

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methods for valuing securities and other assets in circumstances where market quotes are not readily available, and has delegated to PIMCO the responsibility for applying the fair valuation methods. In the event that market quotes or market based valuations are not readily available, and the security or asset cannot be valued pursuant to a Board approved valuation method, the value of the security or asset will be determined in good faith by the Valuation Oversight Committee of the Board, generally based on recommendations provided by PIMCO. Market quotes are considered not readily available in circumstances where there is an absence of current or reliable market-based data (e.g., trade information, bid/ask information, broker quotes, Pricing Services prices), including where events occur after the close of the relevant market, but prior to the NYSE Close, that materially affect the values of the Portfolio’s securities or assets. In addition, market quotes are considered not readily available when, due to extraordinary circumstances, the exchanges or markets on which the securities trade do not open for trading for the entire day and no other market prices are available. The Board of Trustees has delegated to PIMCO the responsibility for monitoring significant events that may materially affect the values of the Portfolio’s securities or assets and for determining whether the value of the applicable securities or assets should be reevaluated in light of such significant events.
When the Portfolio uses fair valuation to determine the value of a portfolio security or other asset for purposes of calculating its NAV, such investments will not be priced on the basis of quotes from the primary market in which they are traded, but rather may be priced by another method that the Board or persons acting at their direction believe reflects fair value. Fair valuation may require subjective determinations about the value of a security. While the Trust’s policy is intended to result in a calculation of the Portfolio’s NAV that fairly reflects security values as of the time of pricing, the Trust cannot ensure that fair values determined by the Board of Trustees or persons acting at their direction would accurately reflect the price that the Portfolio could obtain for a security if it were to dispose of that security as of the time of pricing (for instance, in a forced or distressed sale). The prices used by the Portfolio may differ from the value that would be realized if the securities were sold. The Portfolio’s use of fair valuation may also help to deter “stale price arbitrage” as discussed above under “Frequent or Excessive Purchases, Exchanges and Redemptions.”
Tax Consequences
The Portfolio intends to qualify as a regulated investment company annually and to elect to be treated as a regulated investment company for federal income tax purposes. As such, the Portfolio generally will not pay federal income tax on the income and gains it pays as dividends to its shareholders.
The Portfolio intends to diversify its investments in a manner intended to comply with tax requirements generally applicable to mutual funds. In addition, the Portfolio will diversify its investments so that on the last day of each quarter of a calendar year, no more than 55% of the value of its total assets is represented by any one investment, no more than 70% is represented by any two investments, no more than 80% is represented by any three investments, and no more than 90% is
represented by any four investments. For this purpose, securities of a single issuer are treated as one investment and each U.S. Government agency or instrumentality is treated as a separate issuer. Any security issued, guaranteed, or insured (to the extent so guaranteed or insured) by the U.S. Government or any agency or instrumentality of the U.S. Government is treated as a security issued by the U.S. Government or its agency or instrumentality, whichever is applicable.
If the Portfolio fails to meet the diversification requirement under Section 817(h) of the Code, income with respect to Variable Contracts invested in the Portfolio at any time during the calendar quarter in which the failure occurred could become currently taxable to the owners of the Variable Contracts and income for prior periods with respect to such contracts also could be taxable, most likely in the year of the failure to achieve the required diversification. Other adverse tax consequences could also ensue.
Please refer to the prospectus for the Separate Account and Variable Contract for information regarding the federal income tax treatment of Variable Contracts. See “Taxation” in the Portfolio’s SAI for more information on taxes.
This “Tax Consequences” section relates only to federal income tax; the consequences under other tax laws may differ. Shareholders should consult their tax advisors as to the possible application of foreign, state and local income tax laws to Portfolio dividends and capital distributions. Please see “Taxation” in the Portfolio’s SAI for additional information regarding the tax aspects of investing in the Portfolio.
Characteristics and Risks of Securities and Investment Techniques
This section provides additional information about some of the principal investments and related risks of the Portfolio described under “Portfolio Summary” and “Description of Principal Risks” above. It also describes characteristics and risks of additional securities and investment techniques that may be used by the Portfolio from time to time. Most of these securities and investment techniques described herein are discretionary, which means that PIMCO can decide whether to use them or not. This prospectus does not attempt to disclose all of the various types of securities and investment techniques that may be used by the Portfolio. As with any mutual fund, investors in the Portfolio rely on the professional investment judgment and skill of PIMCO and the individual portfolio managers. Please see “Investment Objectives and Policies” in the SAI for more detailed information about the securities and investment techniques described in this section and about other strategies and techniques that may be used by the Portfolio.
Investors should be aware that the investments made by the Portfolio and the results achieved by the Portfolio at any given time are not expected to be the same as those made by other funds for which PIMCO acts as investment adviser, including funds with names, investment objectives and policies similar to the Portfolio. This may be attributable to a wide variety of factors, including, but not limited to, the use of a different portfolio management team or strategy, when a particular fund commenced operations or the size of a particular fund, in each case as compared to other similar funds. Significant shareholder

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purchases and redemptions may adversely impact the Portfolio’s portfolio management. For example, the Portfolio may be forced to sell a comparatively large portion of its portfolio to meet significant shareholder redemptions, or hold a comparatively large portion of its portfolio in cash due to significant shareholder purchases, in each case when the Portfolio otherwise would not seek to do so. Such shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. Such transactions may also increase the Portfolio’s transaction costs, accelerate the realization of taxable income if sales of securities resulted in gains, or otherwise cause the Portfolio to perform differently than intended. Similarly, significant shareholder purchases may adversely affect the Portfolio’s performance to the extent the Portfolio is delayed in investing new cash and, as a result, holds a proportionally larger cash position than under ordinary circumstances and such impact may be heightened in funds of funds. While such risks may apply to Portfolios of any size, such risks are heightened in Portfolios with fewer assets under management. In addition, new Portfolios may not be able to fully implement their investment strategy immediately upon commencing investment operations, which could reduce investment performance.
More generally, the Portfolio may be adversely affected when a large shareholder purchases or redeems large amounts of shares, which can occur at any time and may impact the Portfolio in the same manner as a high volume of purchase or redemption requests. Such large shareholders include, but are not limited to, other funds, institutional investors, and asset allocators who make investment decisions on behalf of underlying clients. Large shareholder transactions may cause the Portfolio to make investment decisions at inopportune times or prices or miss attractive investment opportunities. In addition, such transactions may also cause the Portfolio to sell certain assets in order to meet purchase or redemption requests, which could indirectly affect the liquidity of the Portfolio’s portfolio. Such transactions may also increase the Portfolio’s transaction costs, decrease economies of scale, accelerate the realization of taxable income, or otherwise cause the Portfolio to perform differently than intended. While large shareholder transactions may be more frequent under certain circumstances, the Portfolio is generally subject to the risk that a large shareholder can purchase or redeem a significant percentage of Portfolio shares at any time. Moreover, the Portfolio is subject to the risk that other shareholders may make investment decisions based on the choices of a large shareholder, which could exacerbate any potential negative effects experienced by the Portfolio.
Investment Selection
The Portfolio seeks maximum total return. The total return sought by the Portfolio consists of both income earned on the Portfolio’s investments and capital appreciation, if any, arising from increases in the market value of the Portfolio’s holdings. Capital appreciation of fixed income securities generally results from decreases in market interest rates, foreign currency appreciation, or improving credit fundamentals for a particular market sector or security.
In selecting securities for the Portfolio, PIMCO develops an outlook for interest rates, currency exchange rates and the economy; analyzes credit and call risks; and uses other security selection techniques. The proportion of the Portfolio’s assets committed to investment in securities with particular characteristics (such as quality, sector, interest rate or maturity) varies based on PIMCO’s outlook for the U.S. economy and the economies of other countries in the world, the financial markets and other factors.
With respect to fixed income investing, PIMCO attempts to identify areas of the bond market that are undervalued relative to the rest of the market. PIMCO identifies these areas by grouping Fixed Income Instruments into sectors such as money markets, governments, corporates, mortgages, asset-backed and international. In seeking to identify undervalued currencies, PIMCO may consider many factors, including but not limited to longer-term analysis of relative interest rates, inflation rates, real exchange rates, purchasing power parity, trade account balances and current account balances, as well as other factors that influence exchange rates such as flows, market technical trends and government policies. Sophisticated proprietary software then assists in evaluating sectors and pricing specific investments. Once investment opportunities are identified, PIMCO will shift assets among sectors depending upon changes in relative valuations, credit spreads and other factors. There is no guarantee that PIMCO’s investment selection techniques will produce the desired results.
Fixed Income Instruments
“Fixed Income Instruments,” as used generally in this prospectus, includes:
securities issued or guaranteed by the U.S. Government, its agencies or government-sponsored enterprises (“U.S. Government Securities”);
corporate debt securities of U.S. and non-U.S. issuers, including convertible securities and corporate commercial paper;
mortgage-backed and other asset-backed securities;
inflation-indexed bonds issued both by governments and corporations;
structured notes, including hybrid or “indexed” securities and event-linked bonds;
bank capital and trust preferred securities;
loan participations and assignments;
delayed funding loans and revolving credit facilities;
bank certificates of deposit, fixed time deposits and bankers’ acceptances;
repurchase agreements on Fixed Income Instruments and reverse repurchase agreements on Fixed Income Instruments;
debt securities issued by states or local governments and their agencies, authorities and other government-sponsored enterprises;
obligations of non-U.S. governments or their subdivisions, agencies and government-sponsored enterprises; and
obligations of international agencies or supranational entities.

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Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury.
The Portfolio, to the extent permitted by the 1940 Act, or exemptive relief therefrom, may invest in derivatives based on Fixed Income Instruments.
Duration
Duration is a measure used to determine the sensitivity of a security’s price to changes in interest rates that incorporates a security’s yield, coupon, final maturity and call features, among other characteristics. The longer a security’s duration, the more sensitive it will be to changes in interest rates. Similarly, a portfolio with a longer average portfolio duration will be more sensitive to changes in interest rates than a portfolio with a shorter average portfolio duration. By way of example, the price of a bond portfolio with an average duration of eight years would be expected to fall approximately 8% if interest rates rose by one percentage point. Similarly, the price of a bond portfolio with an average duration of fifteen years would be expected to fall approximately 15% if interest rates rose by one percentage point. Conversely, the price of a bond portfolio with an average duration of negative three years would be expected to rise approximately 3% if interest rates rose by one percentage point. The maturity of a security, another commonly used measure of price sensitivity, measures only the time until final payment is due, whereas duration takes into account the pattern of all payments of interest and principal on a security over time, including how these payments are affected by prepayments and by changes in interest rates, as well as the time until an interest rate is reset (in the case of variable-rate securities). PIMCO uses an internal model for calculating duration, which may result in a different value for the duration of an index compared to the duration calculated by the index provider or another third party.
U.S. Government Securities
U.S. Government Securities are obligations of, or guaranteed by, the U.S. Government, its agencies or government-sponsored enterprises. The U.S. Government does not guarantee the NAV of the Portfolio’s shares. U.S. Government Securities are subject to market and interest rate risk, as well as varying degrees of credit risk. Some U.S. Government Securities are issued or guaranteed by the U.S. Treasury and are supported by the full faith and credit of the United States. Other types of U.S. Government Securities are supported by the full faith and credit of the United States (but not issued by the U.S. Treasury). These securities may have less credit risk than U.S. Government Securities not supported by the full faith and credit of the United States. Such other types of U.S. Government Securities are: (1) supported by the ability of the issuer to borrow from the U.S. Treasury; (2) supported only by the credit of the issuing agency, instrumentality or government-sponsored corporation; or (3) supported by the United States in some other way. These securities may be subject to greater credit risk. U.S. Government Securities include zero coupon securities, which do not distribute interest on a current basis and tend to be subject to greater market risk than interest-paying securities of similar maturities.
Securities issued by U.S. Government agencies or government-sponsored enterprises may not be guaranteed by the U.S. Treasury. Government National Mortgage Association (“GNMA”), a wholly-owned U.S. Government corporation, is authorized to guarantee, with the full faith and credit of the U.S. Government, the timely payment of principal and interest on securities issued by institutions approved by GNMA and backed by pools of mortgages insured by the Federal Housing Administration or guaranteed by the Department of Veterans Affairs. Government-related guarantors (i.e., not backed by the full faith and credit of the U.S. Government) include the Federal National Mortgage Association (“FNMA”) and the Federal Home Loan Mortgage Corporation (“FHLMC”). Pass-through securities issued by FNMA are guaranteed as to timely payment of principal and interest by FNMA but are not backed by the full faith and credit of the U.S. Government. FHLMC guarantees the timely payment of interest and ultimate collection of principal, but its participation certificates are not backed by the full faith and credit of the U.S. Government. Under the direction of the Federal Housing Finance Agency, FNMA and FHLMC have entered into a joint initiative to develop a common securitization platform for the issuance of a uniform mortgage-backed security (the “Single Security Initiative”) that aligns the characteristics of FNMA and FHLMC certificates. The Single Security Initiative was implemented in June 2019, and the effects it may have on the market for mortgage-backed securities are uncertain.
Municipal Bonds
Municipal Bonds are generally issued by states, territories, possessions and local governments and their agencies, authorities and other instrumentalities. Municipal Bonds are subject to interest rate, credit and market risk, uncertainties related to the tax status of a Municipal Bond or the rights of investors invested in these securities. The ability of an issuer to make payments could be affected by litigation, legislation or other political events or the bankruptcy of the issuer. In addition, imbalances in supply and demand in the municipal market may result in a deterioration of liquidity and a lack of price transparency in the market. At certain times, this may affect pricing, execution and transaction costs associated with a particular trade. The secondary market for municipal bonds, particularly the lower rate bonds, also tends to be less well-developed and less liquid than many other securities markets, which may adversely affect the ability of the Portfolio to sell its bonds at attractive prices or value municipal bonds. The value of certain municipal securities, in particular general obligation debt, may also be adversely affected by rising health care costs, increasing unfunded pension liabilities, changes in accounting standards and by the phasing out of federal programs providing financial support. Lower rated Municipal Bonds are subject to greater credit and market risk than higher quality Municipal Bonds. The types of Municipal Bonds in which the Portfolio may invest include municipal lease obligations, municipal general obligation bonds, municipal essential service revenue bonds, municipal cash equivalents, and pre-refunded and escrowed to maturity Municipal Bonds. The Portfolio may also invest in industrial development bonds, which are Municipal Bonds issued by a government agency on behalf of a private sector company and, in most cases, are not backed by

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the credit of the issuing municipality and may therefore involve more risk. The Portfolio may also invest in securities issued by entities whose underlying assets are Municipal Bonds.
Pre-refunded Municipal Bonds are tax-exempt bonds that have been refunded to a call date on or before the final maturity of principal and remain outstanding in the municipal market. The payment of principal and interest of the pre-refunded Municipal Bonds held by the Portfolio is funded from securities in a designated escrow account that holds U.S. Treasury securities or other obligations of the U.S. Government (including its agencies and instrumentalities (“Agency Securities”)). As the payment of principal and interest is generated from securities held in a designated escrow account, the pledge of the municipality has been fulfilled and the original pledge of revenue by the municipality is no longer in place. The escrow account securities pledged to pay the principal and interest of the pre-refunded Municipal Bond do not guarantee the price movement of the bond before maturity. Issuers of municipal bonds refund in advance of maturity the outstanding higher cost debt and issue new, lower cost debt, placing the proceeds of the lower cost issuance into an escrow account to pre-refund the older, higher cost debt. Investment in pre-refunded Municipal Bonds held by the Portfolio may subject the Portfolio to interest rate risk, market risk and credit risk.
In addition, while a secondary market exists for pre-refunded Municipal Bonds, if the Portfolio sells pre-refunded Municipal Bonds prior to maturity, the price received may be more or less than the original cost, depending on market conditions at the time of sale.
The Portfolio may invest in trust certificates issued in tender option bond programs. In these programs, a trust typically issues two classes of certificates and uses the proceeds to purchase municipal securities having relatively long maturities and bearing interest at a fixed interest rate substantially higher than prevailing short-term tax-exempt rates. There is a risk that the Portfolio investing in a tender option bond program will not be considered the owner of a tender option bond for federal income tax purposes, and thus will not be entitled to treat such interest as exempt from federal income tax. Certain tender option bonds may be illiquid or may become illiquid as a result of, among other things, a credit rating downgrade, a payment default or a disqualification from tax-exempt status.
The Portfolio’s investment in the securities issued by a tender option bond trust may involve greater risk and volatility than an investment in a fixed rate bond, and the value of such securities may decrease significantly when market interest rates increase. Tender option bond trusts could be terminated due to market, credit or other events beyond the Portfolio’s control, which could require the Portfolio to dispose of portfolio investments at inopportune times and prices. The Portfolio may use a tender option bond program as a way of achieving leverage in its portfolio, in which case the Portfolio will be subject to leverage risk.
In December 2013, regulators finalized rules implementing Section 619 (the “Volcker Rule”) and Section 941 (the “Risk Retention Rules”) of the Dodd-Frank Wall Street Reform and Consumer Protection Act. Both the Volcker Rule and the Risk Retention Rules apply to tender option bond programs and place restrictions on the way certain sponsors may
participate in tender option bond programs. Specifically, the Volcker Rule generally prohibits banking entities from engaging in proprietary trading or from acquiring or retaining an ownership interest in, or sponsoring, a hedge fund or private equity fund (“covered fund”), subject to certain exemptions and limitations. Tender option bond programs generally are considered to be covered funds under the Volcker Rule, and, thus, may not be sponsored by a banking entity absent an applicable exemption. The Volcker Rule does not provide for any exemption that would allow banking entities to sponsor tender option bonds in the same manner as they did prior to the Volcker Rule’s compliance date, which was July 21, 2017.
Mortgage-Related and Other Asset-Backed Securities
Mortgage-related securities include mortgage pass-through securities, collateralized mortgage obligations (“CMOs”), commercial mortgage-backed securities, mortgage dollar rolls, CMO residuals, stripped mortgage-backed securities (“SMBSs”) and other securities that directly or indirectly represent a participation in, or are secured by and payable from, mortgage loans on real property.
The value of some mortgage-related and other asset-backed securities may be particularly sensitive to changes in prevailing interest rates. Early repayment of principal on some mortgage-related securities may expose the Portfolio to a lower rate of return upon reinvestment of principal. When interest rates rise, the value of a mortgage-related security generally will decline; however, when interest rates are declining, the value of mortgage-related securities with prepayment features may not increase as much as other fixed income securities. The rate of prepayments on underlying mortgages will affect the price and volatility of a mortgage-related security, and may shorten or extend the effective maturity of the security beyond what was anticipated at the time of purchase. If unanticipated rates of prepayment on underlying mortgages increase the effective maturity of a mortgage-related security, the volatility of the security can be expected to increase. See “Extension Risk” and “Prepayment Risk” below. The values of these securities may fluctuate in response to the market’s perception of the creditworthiness of the issuers. Additionally, although mortgages and mortgage-related securities are generally supported by some form of government or private guarantee and/or insurance, there is no assurance that guarantors or insurers will meet their obligations.
Extension Risk. Mortgage-related and other asset-backed securities are subject to Extension Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation later than expected. This may occur when interest rates rise. This may negatively affect Portfolio returns, as the value of the security decreases when principal payments are made later than expected. In addition, because principal payments are made later than expected, the Portfolio may be prevented from investing proceeds it would otherwise have received at a given time at the higher prevailing interest rates.
Prepayment Risk. Mortgage-related and other asset-backed securities are subject to Prepayment Risk, which is the risk that the issuer of such a security pays back the principal of such an obligation earlier than expected (due to the sale of the underlying

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property, refinancing, or foreclosure). This may occur when interest rates decline. Prepayment may expose the Portfolio to a lower rate of return upon reinvestment of principal. Also, if a security subject to prepayment has been purchased at a premium, the value of the premium would be lost in the event of prepayment.
One type of SMBS has one class receiving all of the interest from the mortgage assets (the interest-only, or “IO” class), while the other class will receive all of the principal (the principal-only, or “PO” class). The yield to maturity on an IO class is extremely sensitive to the rate of principal payments (including prepayments) on the underlying mortgage assets, and a rapid rate of principal payments may have a material adverse effect on the Portfolio’s yield to maturity from these securities. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO or inverse floater securities.
The Portfolio may invest in each of collateralized bond obligations (“CBOs”), collateralized loan obligations (“CLOs”), other collateralized debt obligations (“CDOs”) and other similarly structured securities. CBOs, CLOs and other CDOs are types of asset-backed securities. A CBO is a trust which is backed by a diversified pool of high-risk, below investment grade fixed income securities. A CLO is a trust typically collateralized by a pool of loans, which may include, among others, domestic and foreign senior secured loans, senior unsecured loans, and subordinate corporate loans, including loans that may be rated below investment grade or equivalent unrated loans. Other CDOs are trusts backed by other types of assets representing obligations of various parties. The Portfolio may invest in other asset-backed securities that have been offered to investors.
Privately Issued Mortgage-Related Securities. Pools created by non-governmental issuers generally offer a higher rate of interest than government and government-related pools because there are no direct or indirect government or agency guarantees of payments in such pools. Privately issued mortgage-related securities are not subject to the same underwriting requirements for the underlying mortgages that are applicable to those mortgage-related securities that have a government or government-sponsored entity guarantee. As a result, the mortgage loans underlying privately issued mortgage-related securities may, and frequently do, have less favorable collateral, credit risk or other underwriting characteristics than government or government-sponsored mortgage-related securities and have wider variances in a number of terms including interest rate, term, size, purpose and borrower characteristics. The risk of nonpayment is greater for mortgage-related securities that are backed by loans that were originated under weak underwriting standards, including loans made to borrowers with limited means to make repayment. A level of risk exists for all loans, although, historically, the poorest performing loans have been those classified as subprime. Privately issued mortgage-related securities are not traded on an exchange and there may be a limited market for the securities, especially when there is a perceived weakness in the mortgage and real
estate market sectors. Without an active trading market, mortgage-related securities held in the Portfolio’s portfolio may be particularly difficult to value because of the complexities involved in assessing the value of the underlying mortgage loans.
Privately Issued Mortgage-Related Securities include securities that reflect an interest in, and are secured by, mortgage loans on commercial real property. Many of the risks of investing in commercial mortgage-backed securities reflect the risks of investing in the real estate securing the underlying mortgage loans. These risks reflect the effects of local and other economic conditions on real estate markets, the ability of tenants to make loan payments, and the ability of a property to attract and retain tenants.
Loan Participations and Assignments
The Portfolio may invest in fixed- and floating-rate loans, which investments generally will be in the form of loan participations and assignments of all or portions of such loans. Participations and assignments involve special types of risk, including extension risk, prepayment risk, credit risk, interest rate risk, liquidity risk, and the risks of being a lender. Loans are subject to the risk that scheduled interest or principal payments will not be made in a timely manner or at all, either of which may adversely affect the value of the loan. In addition, the collateral underlying a loan may be unavailable or insufficient to satisfy a borrower’s obligation, and the Portfolio could become part owner of any collateral if a loan is foreclosed, subjecting the Portfolio to costs associated with owning and disposing of the collateral. If the Portfolio purchases a participation, it may only be able to enforce its rights through the lender, and may assume the credit risk of the lender in addition to the borrower.
Reinvestment
The Portfolio may be subject to the risk that the returns of the Portfolio will decline during periods of falling interest rates because the Portfolio may have to reinvest the proceeds from matured, traded or called debt obligations at interest rates below the Portfolio’s current earnings rate. For instance, when interest rates decline, an issuer of debt obligations may exercise an option to redeem securities prior to maturity, thereby forcing the Portfolio to invest in lower-yielding securities. The Portfolio also may choose to sell higher-yielding portfolio securities and to purchase lower-yielding securities to achieve greater portfolio diversification, because the Portfolio’s portfolio manager believes the current holdings are overvalued or for other investment-related reasons. A decline in the returns received by the Portfolio from its investments is likely to have an adverse effect on the Portfolio’s NAV, yield and total return.
Focused Investment
To the extent that the Portfolio focuses its investments in a particular sector, the Portfolio may be susceptible to loss due to adverse developments affecting that sector. These developments include, but are not limited to, governmental regulation; inflation; rising interest rates; cost increases in raw materials, fuel and other operating expenses; technological innovations that may render existing products and

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equipment obsolete; competition from new entrants; high research and development costs; increased costs associated with compliance with environmental or other governmental regulations; and other economic, business or political developments specific to that sector. Furthermore, the Portfolio may invest a substantial portion of its assets in companies in related sectors that may share common characteristics, are often subject to similar business risks and regulatory burdens, and whose securities may react similarly to the types of developments described above, which will subject the Portfolio to greater risk. The Portfolio also will be subject to focused investment risk to the extent that it invests a substantial portion of its assets in a particular issuer, market, asset class, country or geographic region.
Corporate Debt Securities
Corporate debt securities are subject to the risk of the issuer’s inability to meet principal and interest payments on the obligation and may also be subject to price volatility due to such factors as interest rate sensitivity, market perception of the creditworthiness of the issuer and general market liquidity. When interest rates rise, the value of corporate debt securities can be expected to decline. Debt securities with longer maturities tend to be more sensitive to interest rate movements than those with shorter maturities. In addition, certain corporate debt securities may be highly customized and as a result may be subject to, among others, liquidity and pricing transparency risks.
High Yield Securities and Distressed Companies
Securities rated lower than Baa by Moody’s, or equivalently rated by S&P or Fitch, are sometimes referred to as “high yield securities” or “junk bonds.” Issuers of these securities may be distressed and undergoing restructuring, bankruptcy or other proceedings in an attempt to avoid insolvency. Investing in these securities involves special risks in addition to the risks associated with investments in higher-rated fixed income securities. While offering a greater potential opportunity for capital appreciation and higher yields, high yield and distressed company securities typically entail greater potential price volatility and may be less liquid than higher-rated securities. High yield securities and debt securities of distressed companies may be regarded as predominately speculative with respect to the issuer’s continuing ability to meet principal and interest payments. They may also be more susceptible to real or perceived adverse economic and competitive industry conditions than higher-rated securities. The Portfolio may invest in securities that are in default with respect to the payment of interest or repayment of principal, or present an imminent risk of default with respect to such payments. Issuers of securities in default may fail to resume principal or interest payments, in which case the Portfolio may lose its entire investment.
The market values of high yield securities tend to reflect individual developments of the issuer to a greater extent than do higher-quality securities, which tend to react mainly to fluctuations in the general level of interest rates. In addition, lower-quality debt securities tend to be more sensitive to general economic conditions. Certain emerging market governments that issue high yield securities in which the Portfolio may invest are among the largest debtors to commercial banks, foreign
governments and supranational organizations, such as the World Bank, and may not be able or willing to make principal and/or interest payments as they come due.
Variable and Floating Rate Securities
Variable and floating rate securities are securities that pay interest at rates that adjust whenever a specified interest rate changes and/or that reset on predetermined dates (such as the last day of a month or a calendar quarter). In addition to senior loans, variable- and floating-rate instruments may include, without limit, instruments such as catastrophic and other event-linked bonds, bank capital securities, unsecured bank loans, corporate bonds, money market instruments and certain types of mortgage-related and other asset-backed securities. The Portfolio may invest in floating rate debt instruments (“floaters”) and engage in credit spread trades. A credit spread trade is an investment position relating to a difference in the prices or interest rates of two bonds or other securities, in which the value of the investment position is determined by changes in the difference between the prices or interest rates as the case may be, of the respective securities. Variable and floating rate securities generally are less sensitive to interest rate changes but may decline in value if their interest rates do not rise as much, or as quickly, as interest rates in general. Conversely, floating rate securities will not generally increase in value if interest rates decline. The Portfolio may also invest in inverse floating rate debt instruments (“inverse floaters”). An inverse floater may exhibit greater price volatility than a fixed rate obligation of similar credit quality. The Portfolio may invest up to 5% of its total assets in any combination of mortgage-related or other asset-backed IO, PO, or inverse floater securities. Additionally, the Portfolio may also invest, without limitation, in residual interest bonds. Residual interest bonds are a type of inverse floater. See “Municipal Bonds.”
 Inflation-Indexed Bonds
Inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, which are more fully described below) are fixed income securities whose principal value is periodically adjusted according to the rate of inflation. If the index measuring inflation falls, the principal value of inflation-indexed bonds (other than municipal inflation-indexed bonds and certain corporate inflation-indexed bonds) will be adjusted downward, and consequently the interest payable on these securities (calculated with respect to a smaller principal amount) will be reduced. Repayment of the original bond principal upon maturity (as adjusted for inflation) is guaranteed in the case of TIPS. For bonds that do not provide a similar guarantee, the adjusted principal value of the bond repaid at maturity may be less than the original principal.
TIPS may also be divided into individual zero-coupon instruments for each coupon or principal payment (known as “iSTRIPS”). An iSTRIP of the principal component of a TIPS issue will retain the embedded deflation floor that will allow the holder of the security to receive the greater of the original principal or inflation-adjusted principal value at maturity. iSTRIPS may be less liquid than conventional TIPS because they are a small component of the TIPS market.

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Municipal inflation-indexed securities are municipal bonds that pay coupons based on a fixed rate plus CPI. With regard to municipal inflation-indexed bonds and certain corporate inflation-indexed bonds, the inflation adjustment is typically reflected in the semi-annual coupon payment. As a result, the principal value of municipal inflation-indexed bonds and such corporate inflation-indexed bonds does not adjust according to the rate of inflation. At the same time, the value of municipal inflation-indexed securities and such corporate inflation indexed securities generally will not increase if the rate of inflation decreases. Because municipal inflation-indexed securities and corporate inflation-indexed securities are a small component of the municipal bond and corporate bond markets, respectively, they may be less liquid than conventional municipal and corporate bonds.
The value of inflation-indexed bonds is expected to change in response to changes in real interest rates. Real interest rates are tied to the relationship between nominal interest rates and the rate of inflation. If nominal interest rates increase at a faster rate than inflation, real interest rates may rise, leading to a decrease in value of inflation-indexed bonds. Any increase in the principal amount of an inflation-indexed bond will be considered taxable ordinary income, even though investors do not receive their principal until maturity.
Event-Linked Exposure
The Portfolio may obtain event-linked exposure by investing in “event-linked bonds” or “event-linked swaps” or by implementing “event-linked strategies.” Event-linked exposure results in gains or losses that typically are contingent, or formulaically related to defined trigger events. Examples of trigger events include hurricanes, earthquakes, weather-related phenomena, or statistics related to such events. Some event-linked bonds are commonly referred to as “catastrophe bonds.” If a trigger event occurs, the Portfolio may lose a portion or its entire principal invested in the bond or notional amount on a swap. Event-linked exposure often provides for an extension of maturity to process and audit loss claims where a trigger event has, or possibly has, occurred. An extension of maturity may increase volatility. Event-linked exposure may also expose the Portfolio to certain unanticipated risks including credit risk, counterparty risk, adverse regulatory or jurisdictional interpretations, and adverse tax consequences. Event-linked exposure may also be subject to liquidity risk.
Convertible and Equity Securities
Common stock represents equity ownership in a company and typically provides the common stockholder the power to vote on certain corporate actions, including the election of the company’s directors. Common stockholders participate in company profits through dividends and, in the event of bankruptcy, distributions, on a pro-rata basis after other claims are satisfied. Many factors affect the value of common stock, including earnings, earnings forecasts, corporate events and factors impacting the issuer’s industry and the market generally. Common stock generally has the greatest appreciation and depreciation potential of all corporate securities.
The Portfolio may invest in convertible securities and equity securities, as well as securities related to equities. Equity-related securities include securities having an equity component (e.g., hybrids, bank capital) and equity derivatives. The PIMCO Total Return Portfolio may not purchase common stock, but this limitation does not prevent the Portfolio from holding common stock obtained through the conversion of convertible securities or common stock that is received as part of a corporate reorganization or debt restructuring (for example, as may occur during bankruptcies or distressed situations).  Convertible securities are generally preferred securities and other securities, including fixed income securities and warrants, that are convertible into or exercisable for common stock at a stated price or rate. The price of a convertible security will normally vary in some proportion to changes in the price of the underlying common stock because of this conversion or exercise feature. However, the value of a convertible security may not increase or decrease as rapidly as the underlying common stock. A convertible security will normally also provide income and is subject to interest rate risk. Convertible securities may be lower-rated securities subject to greater levels of credit risk. The Portfolio may be forced to convert a security before it would otherwise choose, which may have an adverse effect on the Portfolio’s ability to achieve its investment objective.
“Synthetic” convertible securities are selected based on the similarity of their economic characteristics to those of a traditional convertible security due to the combination of separate securities that possess the two principal characteristics of a traditional convertible security, i.e., an income-producing security (“income-producing component”) and the right to acquire an equity security (“convertible component”). The income-producing component is achieved by investing in non-convertible, income-producing securities such as bonds, preferred securities and money market instruments, which may be represented by derivative instruments. The convertible component is achieved by investing in securities or instruments such as warrants or options to buy common stock at a certain exercise price, or options on a stock index. A simple example of a synthetic convertible security is the combination of a traditional corporate bond with a warrant to purchase equity securities of the issuer of the bond. The Portfolio may also purchase synthetic securities created by other parties, typically investment banks, including convertible structured notes. The income-producing and convertible components of a synthetic convertible security may be issued separately by different issuers and at different times.
Preferred and other senior securities generally entitle the holder to receive, in preference to the holders of other securities such as common stocks, dividends and a fixed share of the proceeds resulting from a liquidation of the company. Preferred and other senior securities may pay fixed or adjustable rates of return. Preferred and other senior securities are subject to issuer-specific and market risks applicable generally to equity securities. In addition, a company’s preferred and other senior securities generally pay dividends only after the company makes required payments to holders of its bonds and other debt. For this reason, the value of preferred and other senior securities will usually react more strongly than bonds and other debt to actual or perceived changes in the company’s financial condition or prospects. In addition, preferred and other senior securities often have special redemption

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rights allowing issuers to redeem such securities at par earlier than scheduled. If these rights are exercised, the Portfolio may have to reinvest proceeds in less attractive securities.
Among other risks described in this prospectus, the following issues are particularly associated with investments in preferred and other senior securities.
Deferral and Omission of Distributions.Preferred and other senior securities may include features permitting or requiring the issuer to defer or omit distributions. Among other things, such deferral or omission may result in adverse tax consequences for the Portfolio.
Limited Voting Rights.Preferred and other senior securities generally do not have voting rights with respect to the issuer unless dividends have been in arrears for certain specified periods of time.
In the future, preferred or other senior securities may be offered with features different from those described above, and as such, may entail different risks. Over longer periods of time, certain types of preferred or other senior securities may become more scarce or less liquid as a result of legislative changes. Such events may result in losses to the Portfolio as the prices of securities it holds may be negatively affected. Revisions to bank capital requirements by international regulatory bodies, to the extent they are adopted in the United States, may also negatively impact the market for certain preferred or senior securities.
While some countries or companies may be regarded as favorable investments, pure fixed income opportunities may be unattractive or limited due to insufficient supply, or legal or technical restrictions. In such cases, subject to its applicable investment restrictions, the Portfolio may consider convertible securities or equity securities to gain exposure to such investments.
At times, in connection with the restructuring of a preferred security or Fixed Income Instrument either outside of bankruptcy court or in the context of bankruptcy court proceedings, the Portfolio may determine or be required to accept equity securities, such as common stocks, in exchange for all or a portion of a preferred security or Fixed Income Instrument. Depending upon, among other things, PIMCO’s evaluation of the potential value of such securities in relation to the price that could be obtained by the Portfolio at any given time upon sale thereof, the Portfolio may determine to hold such securities in its portfolio.
Equity securities generally have greater price volatility than fixed income securities. The market price of equity securities owned by the Portfolio may go up or down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally or particular industries represented in those markets. The value of an equity security may also decline for a number of reasons which directly relate to the issuer, such as management performance, financial leverage and reduced demand for the issuer’s goods or services.
Foreign (Non-U.S.) Securities
The Portfolio may invest in securities and instruments that are economically tied to foreign (non-U.S.) countries. PIMCO generally considers an instrument to be economically tied to a non-U.S. country if the issuer is a foreign (non-U.S.) government (or any political subdivision, agency, authority or instrumentality of such government), or if the issuer is organized under the laws of a non-U.S. country. The Portfolio’s investments in foreign (non-U.S.) securities may include American Depositary Receipts (“ADRs”), European Depositary Receipts (“EDRs”), Global Depositary Receipts (“GDRs”) and similar securities that represent interests in a non-U.S. company’s securities that have been deposited with a bank or trust and that trade on a U.S. exchange or over-the-counter. ADRs, EDRs and GDRs may be less liquid or may trade at a different price than the underlying securities of the issuer. In the case of money market instruments other than commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the issuer of such money market instruments is organized under the laws of a non-U.S. country. In the case of commercial paper and certificates of deposit, such instruments will be considered economically tied to a non-U.S. country if the “country of exposure” of such instrument is a non-U.S. country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to non-U.S. countries if the underlying assets are foreign currencies (or baskets or indexes of such currencies), or instruments or securities that are issued by foreign governments or issuers organized under the laws of a non-U.S. country (or if the underlying assets are money market instruments other than commercial paper and certificates of deposit, the issuer of such money market instruments is organized under the laws of a non-U.S. country or, in the case of underlying assets that are commercial paper or certificates of deposit, if the “country of exposure” of such money market instrument is a non-U.S. country). A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer.
Investing in foreign (non-U.S.) securities involves special risks and considerations not typically associated with investing in U.S. securities. Investors should consider carefully the substantial risks involved for

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Portfolios that invest in securities issued by foreign companies and governments of foreign countries. These risks include: differences in accounting, auditing and financial reporting standards; generally higher commission rates on foreign portfolio transactions; the possibility of nationalization, expropriation or confiscatory taxation; adverse changes in investment or exchange control regulations; market disruptions; the possibility of security suspensions; and political instability. Individual foreign (non-U.S.) economies may differ favorably or unfavorably from the U.S. economy in such respects as growth of gross domestic product, rates of inflation, capital reinvestment, resources, self-sufficiency and balance of payments position. Other countries' financial infrastructure or settlement systems may be less developed than those of the United States. The securities markets, values of securities, yields and risks associated with foreign (non-U.S.) securities markets may change independently of each other. Also, foreign (non-U.S.) securities and dividends and interest payable on those securities may be subject to foreign taxes, including taxes withheld from payments on those securities. Foreign (non-U.S.) securities often trade with less frequency and volume than domestic securities and therefore may exhibit greater price volatility. Investments in foreign (non-U.S.) securities may also involve higher custodial costs than domestic investments and additional transaction costs with respect to foreign currency conversions. Changes in, or uncertainty concerning, foreign exchange rates also will affect the value of securities denominated or quoted in foreign currencies and in some cases could lead to uncertainty regarding the reliability of issuers’ financial reporting.
The Portfolio also may invest in sovereign debt issued by governments, their agencies or instrumentalities, or other government-related entities. Holders of sovereign debt may be requested to participate in the rescheduling of such debt and to extend further loans to governmental entities. In addition, there is no bankruptcy proceeding by which defaulted sovereign debt may be collected.
Emerging Market Securities.The Portfolio may invest in securities and instruments that are economically tied to developing (or “emerging market”) countries. PIMCO generally considers an instrument to be economically tied to an emerging market country if: the issuer is organized under the laws of an emerging market country; the currency of settlement of the security is a currency of an emerging market country; the security is guaranteed by the government of an emerging market country (or any political subdivision, agency, authority or instrumentality of such government); for an asset-backed or other collateralized security, the country in which the collateral backing the security is located is an emerging market country; or the security’s “country of exposure” is an emerging market country, as determined by the criteria set forth below. With respect to derivative instruments, PIMCO generally considers such instruments to be economically tied to emerging market countries if the underlying assets are currencies of emerging market countries (or baskets or indexes of such currencies), or instruments or securities that are issued or guaranteed by governments of emerging market countries or by entities organized under the laws of emerging market countries or if an instrument’s “country of exposure” is an emerging market
country. A security’s “country of exposure” is determined by PIMCO using certain factors provided by a third-party analytical service provider. The factors are applied in order such that the first factor to result in the assignment of a country determines the “country of exposure.” Both the factors and the order in which they are applied may change in the discretion of PIMCO. The current factors, listed in the order in which they are applied, are: (i) if an asset-backed or other collateralized security, the country in which the collateral backing the security is located; (ii) the “country of risk” of the issuer; (iii) if the security is guaranteed by the government of a country (or any political subdivision, agency, authority or instrumentality of such government), the country of the government or instrumentality providing the guarantee; (iv) the “country of risk” of the issuer’s ultimate parent; or (v) the country where the issuer is organized or incorporated under the laws thereof. “Country of risk” is a separate four-part test determined by the following factors, listed in order of importance: (i) management location; (ii) country of primary listing; (iii) sales or revenue attributable to the country; and (iv) reporting currency of the issuer. PIMCO has broad discretion to identify countries that it considers to qualify as emerging markets. In making investments in emerging market securities, the Portfolio emphasizes those countries with relatively low gross national product per capita and with the potential for rapid economic growth. Emerging market countries are generally located in Asia, Africa, the Middle East, Latin America and Eastern Europe. PIMCO will select the country and currency composition based on its evaluation of relative interest rates, inflation rates, exchange rates, monetary and fiscal policies, trade and current account balances, legal and political developments and any other specific factors it believes to be relevant.
Investing in emerging market securities imposes risks different from, or greater than, risks of investing in domestic securities or in foreign, developed countries. These risks include: smaller market capitalization of securities markets, which may suffer periods of relative illiquidity; significant price volatility; restrictions on foreign investment; possible repatriation of investment income and capital. In addition, foreign investors may be required to register the proceeds of sales; future economic or political crises could lead to price controls, forced mergers, expropriation or confiscatory taxation, seizure, nationalization, or creation of government monopolies. The currencies of emerging market countries may experience significant declines against the U.S. dollar, and devaluation may occur subsequent to investments in these currencies by the Portfolio. Many emerging market countries have experienced substantial, and in some periods extremely high, rates of inflation for many years. Inflation and rapid fluctuations in inflation rates have had, and may continue to have, negative effects on the economies and securities markets of certain emerging market countries.
Additional risks of emerging market securities may include: greater social, economic and political uncertainty and instability; more substantial governmental involvement in the economy; less governmental supervision and regulation; unavailability of currency hedging techniques; companies that are newly organized and small;

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differences in auditing and financial reporting standards, which may result in unavailability of material information about issuers; and less developed legal systems. In addition, emerging securities markets may have different clearance and settlement procedures, which may be unable to keep pace with the volume of securities transactions or otherwise make it difficult to engage in such transactions. Settlement problems may cause the Portfolio to miss attractive investment opportunities, hold a portion of its assets in cash pending investment, or be delayed in disposing of a portfolio security. Such a delay could result in possible liability to a purchaser of the security.
Foreign (Non-U.S.) Currencies
Direct investments in foreign (non-U.S.) currencies or in securities that trade in, or receive revenues in, foreign (non-U.S.) currencies will be subject to currency risk. Foreign currency exchange rates may fluctuate significantly over short periods of time. They generally are determined by supply and demand in the foreign exchange markets and the relative merits of investments in different countries, actual or perceived changes in interest rates and other complex factors. Currency exchange rates also can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Currencies in which the Portfolio’s assets are denominated may be devalued against the U.S. dollar, resulting in a loss to the Portfolio.
Foreign Currency Transactions.The Portfolio may invest in securities denominated in foreign (non-U.S.) currencies, engage in foreign currency transactions on a spot (cash) basis, enter into forward foreign currency exchange contracts, and invest in foreign currency futures contracts and options on foreign currencies and futures. A forward foreign currency exchange contract, which involves an obligation to purchase or sell a specific currency at a future date at a price set at the time of the contract, reduces the Portfolio’s exposure to changes in the value of the currency it will deliver and increases its exposure to changes in the value of the currency it will receive for the duration of the contract. Certain foreign currency transactions may also be settled in cash rather than the actual delivery of the relevant currency. The effect on the value of the Portfolio is similar to selling securities denominated in one currency and purchasing securities denominated in another currency. Foreign currency transactions, like currency exchange rates, can be affected unpredictably by intervention (or the failure to intervene) by U.S. or foreign governments or central banks, or by currency controls or political developments. Such events may prevent or restrict the Portfolio’s ability to enter into foreign currency transactions, force the Portfolio to exit a foreign currency transaction at a disadvantageous time or price or result in penalties for the Portfolio, any of which may result in a loss to the Portfolio. A contract to sell a foreign currency would limit any potential gain that might be realized if the value of the hedged currency increases. The Portfolio may enter into these contracts to hedge against foreign exchange risk, to increase exposure to a foreign currency or to shift exposure to foreign currency fluctuations from one currency to another. Suitable hedging
transactions may not be available in all circumstances and there can be no assurance that the Portfolio will engage in such transactions at any given time or from time to time. Also, such transactions may not be successful and may eliminate any chance for the Portfolio to benefit from favorable fluctuations in relevant foreign currencies. The Portfolio may use one currency (or a basket of currencies) to hedge against adverse changes in the value of another currency (or a basket of currencies) when exchange rates between the two currencies are positively correlated. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable law, enter into certain offsetting positions) to cover its obligations under forward foreign currency exchange contracts.
Redenomination.Continuing uncertainty as to the status of the euro and the European Monetary Union (the “EMU”) has created significant volatility in currency and financial markets generally. Any partial or complete dissolution of the EMU could have significant adverse effects on currency and financial markets and on the values of the Portfolio’s portfolio investments. If one or more EMU countries were to stop using the euro as its primary currency, the Portfolio’s investments in such countries may be redenominated into a different or newly adopted currency. As a result, the value of those investments could decline significantly and unpredictably. In addition, securities or other investments that are redenominated may be subject to currency risk, liquidity risk and risk of improper valuation to a greater extent than similar investments currently denominated in euros. To the extent a currency used for redenomination purposes is not specified in respect of certain EMU-related investments, or should the euro cease to be used entirely, the currency in which such investments are denominated may be unclear, making such investments particularly difficult to value or dispose of. The Portfolio may incur additional expenses to the extent it is required to seek judicial or other clarification of the denomination or value of such securities. There can be no assurance that if the Portfolio earns income or capital gains in a non-U.S. country or PIMCO otherwise seeks to withdraw the Portfolio’s investments from a given country, capital controls imposed by such country will not prevent, or cause significant expense in, doing so.
Repurchase Agreements
The Portfolio may enter into repurchase agreements, in which the Portfolio purchases a security from a bank or broker-dealer, which agrees to repurchase the security at the Portfolio’s cost plus interest within a specified time. If the party agreeing to repurchase should default, the Portfolio will seek to sell the securities which it holds. This could involve procedural costs or delays in addition to a loss on the securities if their value should fall below their repurchase price.

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Reverse Repurchase Agreements, Dollar Rolls and Other Borrowings
The Portfolio may enter into reverse repurchase agreements and dollar rolls, subject to the Portfolio’s limitations on borrowings. A reverse repurchase agreement involves the sale of a security by the Portfolio and its agreement to repurchase the instrument at a specified time and price. A dollar roll is similar except that the counterparty is not obligated to return the same securities as those originally sold by the Portfolio but only securities that are “substantially identical.” Reverse repurchase agreements and dollar rolls may be considered borrowing for some purposes. In accordance with current federal securities laws, rules and staff positions, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO to cover its obligations under reverse repurchase agreements and dollar rolls. Reverse repurchase agreements, dollar rolls and other forms of borrowings may create leveraging risk for the Portfolio.
The Portfolio may borrow money to the extent permitted under the 1940 Act. This means that, in general, the Portfolio may borrow money from banks for any purpose in an amount up to one-third of the Portfolio’s total assets, less all liabilities and indebtedness not represented by senior securities. The Portfolio may also borrow money for temporary administrative purposes in an amount not to exceed 5% of the Portfolio’s total assets. In addition, the Portfolio may borrow from certain other PIMCO funds in inter-fund lending transactions to the extent permitted by an exemptive order from the SEC.
Derivatives
The Portfolio may, but is not required to, use derivative instruments for risk management purposes or as part of its investment strategies. Generally, derivatives are financial contracts whose value depends upon, or is derived from, the value of an underlying asset, reference rate or index, and may relate to stocks, bonds, interest rates, spreads between different interest rates, currencies or currency exchange rates, commodities, and related indexes. Examples of derivative instruments include options contracts, futures contracts, options on futures contracts and swap agreements (including, but not limited to, credit default swaps and swaps on exchange-traded funds). The Portfolio may invest some or all of its assets in derivative instruments, subject to the Portfolio’s objective and policies. A portfolio manager may decide not to employ any of these strategies and there is no assurance that any derivatives strategy used by the Portfolio will succeed. A description of these and other derivative instruments that the Portfolio may use are described under “Investment Objectives and Policies” in the SAI.
The Portfolio’s use of derivative instruments involves risks different from, or possibly greater than, the risks associated with investing directly in securities and other more traditional investments. Certain derivative transactions may have a leveraging effect on the Portfolio. For example, a small investment in a derivative instrument may have a significant impact on the Portfolio’s exposure to interest rates, currency exchange rates or other investments. As a result, a relatively small price movement in a derivative instrument may cause an immediate and substantial loss or gain. The Portfolio may engage in such transactions regardless of
whether the Portfolio owns the asset, instrument or components of the index underlying the derivative instrument. The Portfolio may invest a significant portion of its assets in these types of instruments. If it does, the Portfolio’s investment exposure could far exceed the value of its portfolio securities and its investment performance could be primarily dependent upon securities it does not own. A description of various risks associated with particular derivative instruments is included in “Investment Objectives and Policies” in the SAI. The following provides a more general discussion of important risk factors relating to all derivative instruments that may be used by the Portfolio.
CPI Swap.A CPI swap is a fixed maturity, over-the-counter derivative transaction in which the investor receives the “realized” rate of inflation as measured by the Consumer Price Index for All Urban Consumers (“CPI”) over the life of the swap. The investor in turn pays a fixed annualized rate over the life of the swap. This fixed rate is often referred to as the “breakeven inflation” rate and is generally representative of the difference between treasury yields and TIPS yields of similar maturities at the initiation of the swap. CPI swaps are typically in “bullet” format, where all cash flows are exchanged at maturity. In addition to counterparty risk, CPI swaps are also subject to inflation risk, where the swap can potentially lose value if the realized rate of inflation over the life of the swap is less than the fixed market implied inflation rate (fixed breakeven rate) that the investor agrees to pay at the initiation of the swap.
Management Risk.Derivative products are highly specialized instruments that require investment techniques and risk analyses different from those associated with stocks and bonds. The use of a derivative requires an understanding not only of the underlying instrument but also of the derivative itself, without the benefit of observing the performance of the derivative under all possible market conditions.
Credit Risk.The use of certain derivative instruments involves the risk that a loss may be sustained as a result of the failure of another party to the contract (usually referred to as a “counterparty”) to make required payments or otherwise comply with the contract’s terms. Additionally, a short position in a credit default swap could result in losses if the Portfolio does not correctly evaluate the creditworthiness of the company on which the credit default swap is based.
Liquidity Risk.Liquidity risk exists when a particular derivative instrument is difficult to purchase or sell. If a derivative transaction is particularly large or if the relevant market is illiquid (as is the case with many privately negotiated derivatives), it may not be possible to initiate a transaction or liquidate a position at an advantageous time or price.
Leverage Risk.Because many derivatives have a leverage component, adverse changes in the value or level of the underlying asset, reference rate or index could result in a loss substantially greater than the amount invested in the derivative itself. Certain derivatives have the potential for unlimited loss, regardless of the size of the initial investment. When the Portfolio uses derivatives for leverage, investments in a Portfolio will tend to be more volatile, resulting in larger gains or losses in response to market changes. In accordance with current federal securities laws,

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rules and staff positions, to limit leverage risk, the Portfolio will segregate or “earmark” assets determined to be liquid by PIMCO (or, as permitted by applicable regulation, enter into certain offsetting positions) to cover its obligations under derivative instruments.
Lack of Availability.Because the markets for certain derivative instruments (including markets located in foreign countries) are relatively new and still developing, suitable derivatives transactions may not be available in all circumstances for risk management or other purposes. Upon the expiration of a particular contract, a portfolio manager may wish to retain the Portfolio’s position in the derivative instrument by entering into a similar contract, but may be unable to do so if the counterparty to the original contract is unwilling to enter into the new contract and no other suitable counterparty can be found. There is no assurance that the Portfolio will engage in derivatives transactions at any time or from time to time. The Portfolio’s ability to use derivatives may also be limited by certain regulatory and tax considerations.
Correlation Risk.In certain cases, the value of derivatives may not correlate perfectly, or at all, with the value of the assets, reference rates or indexes they are designed to closely track. For example, a swap agreement on an exchange-traded fund would not correlate perfectly with the index upon which the exchange-traded fund is based because the fund’s return is net of fees and expenses. In this regard, the Portfolio may seek to achieve its investment objectives, in part, by investing in derivatives positions that are designed to closely track the performance (or inverse performance) of an index on a daily basis. However, the overall investment strategies of the Portfolio are not designed or expected to produce returns which replicate the performance (or inverse performance) of the particular index, and the degree of variation could be substantial, particularly over longer periods. There are a number of factors which may prevent the Portfolio, or derivatives or other strategies used by the Portfolio, from achieving a desired correlation (or inverse correlation) with an index. These may include, but are not limited to: (i) the impact of fund fees, expenses and transaction costs, including borrowing and brokerage costs/ bid-ask spreads, which are not reflected in index returns; (ii) differences in the timing of daily calculations of the value of an index and the timing of the valuation of derivatives, securities and other assets held by the Portfolio and the determination of the NAV of Portfolio shares; (iii) disruptions or illiquidity in the markets for derivative instruments or securities in which the Portfolio invests; (iv) the Portfolio having exposure to or holding less than all of the securities in the underlying index and/or having exposure to or holding securities not included in the underlying index; (v) large or unexpected movements of assets into and out of the Portfolio (due to share purchases or redemptions, for example), potentially resulting in the Portfolio being over- or under-exposed to the index; (vi) the impact of accounting standards or changes thereto; (vii) changes to the applicable index that are not disseminated in advance; (viii) a possible need to conform the Portfolio’s portfolio holdings to comply with investment restrictions or policies or regulatory or tax law requirements; and (ix) fluctuations in currency exchange rates.
Market and Other Risks.Like most other investments, derivative instruments are subject to the risk that the market value of the instrument will change in a way detrimental to the Portfolio’s interest. If a portfolio manager incorrectly forecasts the values of securities, currencies or interest rates or other economic factors in using derivatives for the Portfolio, the Portfolio might have been in a better position if it had not entered into the transaction at all. While some strategies involving derivative instruments can reduce the risk of loss, they can also reduce the opportunity for gain or even result in losses by offsetting favorable price movements in other Portfolio investments. The Portfolio may also have to buy or sell a security at a disadvantageous time or price because the Portfolio is legally required to maintain offsetting positions or asset coverage in connection with certain derivatives transactions. The regulation of the derivatives markets has increased over the past several years, and additional future regulation of the derivatives markets may make derivatives more costly, may limit the availability or reduce the liquidity of derivatives, or may otherwise adversely affect the value or performance of derivatives. Any such adverse future developments could impair the effectiveness or raise the costs of the Portfolio’s derivative transactions, or impede the employment of the Portfolio’s derivatives strategies, or adversely affect the Portfolio’s performance.
Other risks in using derivatives include the risk of mispricing or improper valuation of derivatives. Many derivatives, in particular privately negotiated derivatives, are complex and often valued subjectively. Improper valuations can result in increased cash payment requirements to counterparties or a loss of value to the Portfolio. In addition, the Portfolio’s use of derivatives may cause the Portfolio to realize higher amounts of short-term capital gains (generally taxed at ordinary income tax rates) than if the Portfolio had not used such instruments.
Exchange-Traded Notes (ETNs)
The Portfolio may invest in ETNs. ETNs are senior, unsecured, unsubordinated debt securities whose returns are linked to the performance of a particular market benchmark or strategy minus applicable fees. ETNs are traded on an exchange (e.g., the NYSE) during normal trading hours. However, investors can also hold the ETN until maturity. At maturity, the issuer pays to the investor a cash amount equal to the principal amount, subject to the day’s market benchmark or strategy factor.
ETNs do not make periodic coupon payments or provide principal protection. ETNs are subject to credit risk and the value of the ETN may drop due to a downgrade in the issuer’s credit rating, despite the underlying market benchmark or strategy remaining unchanged. The value of an ETN may also be influenced by time to maturity, level of supply and demand for the ETN, volatility and lack of liquidity in underlying assets, changes in the applicable interest rates, changes in the issuer’s credit rating, and economic, legal, political, or geographic events that affect the referenced underlying asset. When the Portfolio invests in ETNs, it will bear its proportionate share of any fees and expenses borne by the ETN. The Portfolio’s decision to sell its ETN holdings may be limited by the availability of a secondary market. ETNs are also subject to tax risk. The IRS and Congress are considering

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PIMCO Variable Insurance Trust

proposals that would change the timing and character of income and gains from ETNs. There may be times when an ETN share trades at a premium or discount to its market benchmark or strategy.
Delayed Funding Loans and Revolving Credit Facilities
The Portfolio may also enter into, or acquire participations in, delayed funding loans and revolving credit facilities, in which a lender agrees to make loans up to a maximum amount upon demand by the borrower during a specified term. These commitments may have the effect of requiring the Portfolio to increase its investment in a company at a time when it might not otherwise decide to do so (including at a time when the company’s financial condition makes it unlikely that such amounts will be repaid). In accordance with current federal securities laws, rules and staff positions, to the extent that the Portfolio is committed to advance additional funds, it will segregate or “earmark” assets determined to be liquid by PIMCO in an amount sufficient to meet such commitments. Delayed funding loans and revolving credit facilities are subject to credit, interest rate and liquidity risk and the risks of being a lender.
When-Issued, Delayed Delivery and Forward Commitment Transactions
The Portfolio may purchase or sell securities that it is eligible to purchase or sell on a when-issued basis, may purchase and sell such securities for delayed delivery and may make contracts to purchase or sell such securities for a fixed price at a future date beyond normal settlement time (forward commitments). When-issued transactions, delayed delivery purchases and forward commitments involve a risk of loss if the value of the securities declines prior to the settlement date. This risk is in addition to the risk that the Portfolio’s other assets will decline in value. Therefore, these transactions may result in a form of leverage and increase the Portfolio’s overall investment exposure. Typically, no income accrues on securities the Portfolio has committed to purchase prior to the time delivery of the securities is made, although the Portfolio may earn income on securities it has segregated or “earmarked” to cover these positions. When the Portfolio has sold a security on a when-issued, delayed delivery, or forward commitment basis, the Portfolio does not participate in future gains or losses with respect to the security. If the other party to a transaction fails to pay for the securities, the Portfolio could suffer a loss. Additionally, when selling a security on a when-issued, delayed delivery, or forward commitment basis without owning the security, the Portfolio will incur a loss if the security’s price appreciates in value such that the security’s price is above the agreed-upon price on the settlement date.
Investment in Other Investment Companies
The Portfolio may invest in securities of other investment companies, such as open-end or closed-end management investment companies, including exchange-traded funds, or in pooled accounts, or other unregistered accounts or investment vehicles to the extent permitted by the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom. The Portfolio may invest in other investment companies to gain broad market or sector exposure, including during
periods when it has large amounts of uninvested cash or when PIMCO believes share prices of other investment companies offer attractive values. As a shareholder of an investment company or other pooled vehicle, the Portfolio may indirectly bear investment advisory fees, supervisory and administrative fees, service fees and other fees which are in addition to the fees the Portfolio pays its service providers.
The Portfolio may invest in certain money market funds and/or short-term bond funds (“Central Funds”), to the extent permitted by the 1940 Act, the rules thereunder or exemptive relief therefrom. The Central Funds are registered investment companies created for use solely by the series of the Trust, PIMCO Funds, PIMCO ETF Trust, PIMCO Equity Series and PIMCO Equity Series VIT, and certain other series of registered investment companies advised by PIMCO, in connection with their cash management activities. The main investments of the Central Funds are money market instruments and short maturity Fixed Income Instruments. The Central Funds may incur expenses related to their investment activities, but do not pay investment advisory or supervisory and administrative fees to PIMCO.
Subject to the restrictions and limitations of the 1940 Act and the rules and regulations thereunder and any exemptive relief therefrom, the Portfolio may, in the future, elect to pursue its investment objective either by investing directly in securities, or by investing in one or more underlying investment vehicles or companies that have substantially similar investment objectives and policies as the Portfolio.
Small-Cap and Mid-Cap Companies
The Portfolio may invest in equity securities of small-capitalization and mid-capitalization companies. The Portfolio considers a small-cap company to be a company with a market capitalization of up to $1.5 billion and a mid-cap company to be a company with a market capitalization of between $1.5 billion and $10 billion. Investments in small-cap and mid-cap companies involve greater risk than investments in large-capitalization companies. Small- and mid-cap companies may not have an established financial history, which can present valuation challenges. The equity securities of small- and mid-cap companies may be subject to increased market fluctuations, due to less liquid markets and more limited managerial and financial resources. The Portfolio’s investment in small- and mid-cap companies may increase the volatility of the Portfolio’s portfolio.
Short Sales
The Portfolio may make short sales as part of its overall portfolio management strategies or to offset a potential decline in value of a security. A short sale involves the sale of a security that is borrowed from a broker or other institution to complete the sale. Short sales expose the Portfolio to the risk that it will be required to acquire, convert or exchange securities to replace the borrowed securities (also known as “covering” the short position) at a time when the securities sold short have appreciated in value, thus resulting in a loss to the Portfolio. In accordance with current federal securities laws, rules and staff positions, when making a short sale (other than a “short sale against the box”) the Portfolio must segregate or “earmark” assets

32  Prospectus | PIMCO Variable Insurance Trust

Prospectus

determined to be liquid by PIMCO or otherwise cover its position in a permissible manner. A short sale is “against the box” to the extent that the Portfolio contemporaneously owns, or has the right to obtain at no added cost, securities identical to those sold short. The Portfolio may engage in short selling to the extent permitted by the 1940 Act and rules and interpretations thereunder and other federal securities laws. To the extent the Portfolio engages in short selling in foreign (non-U.S.) jurisdictions, the Portfolio will do so to the extent permitted by the laws and regulations of such jurisdiction.
Illiquid Investments
The Portfolio may invest up to 15% of its net assets (taken at the time of investment) in illiquid investments that are assets. Certain illiquid investments may require pricing at fair value as determined in good faith under the supervision of the Board of Trustees. A portfolio manager may be subject to significant delays in disposing of illiquid investments and transactions in illiquid investments may entail registration expenses and other transaction costs that are higher than those for transactions in liquid investments. The term “illiquid investments” for this purpose means investments that the Portfolio reasonably expects cannot be sold or disposed of in current market conditions in seven calendar days or less without the sale or disposition significantly changing the market value of the investment. Restricted securities, i.e., securities subject to legal or contractual restrictions on resale, may be illiquid. However, some restricted securities (such as securities issued pursuant to Rule 144A under the Securities Act of 1933, as amended, and certain commercial paper) may be treated as liquid (i.e., classified by the Portfolio in a liquidity category other than “illiquid” pursuant to the Portfolio’s liquidity risk management procedures), although they may be relatively less liquid than registered securities traded on established secondary markets. Additional discussion of illiquid investments and related regulatory limits and requirements is available under “Investment Objectives and Policies” in the SAI.
Loans of Portfolio Securities
For the purpose of achieving income, the Portfolio may lend its portfolio securities to brokers, dealers, and other financial institutions provided that a number of conditions are satisfied, including that the loan is fully collateralized. Please see “Investment Objectives and Policies” in the SAI for details. When the Portfolio lends portfolio securities, its investment performance will continue to reflect changes in the value of the securities loaned, and the Portfolio will also receive a fee or interest on the collateral. Securities lending involves the risk of loss of rights in the collateral or delay in recovery of the collateral if the borrower fails to return the security loaned or becomes insolvent. The Portfolio may pay lending fees to a party arranging the loan, which may be an affiliate of the Portfolio. Cash collateral received by the Portfolio in securities lending transactions may be invested in short-term liquid fixed income instruments or in money market or short-term mutual funds, or similar investment vehicles, including affiliated money market or short-term mutual funds. The Portfolio bears the risk of such investments.
Portfolio Turnover
The length of time the Portfolio has held a particular security is not generally a consideration in investment decisions. A change in the securities held by the Portfolio is known as “portfolio turnover.” When a portfolio manager deems it appropriate and particularly during periods of volatile market movements, the Portfolio may engage in frequent and active trading of portfolio securities to achieve its investment objective. Higher portfolio turnover (e.g., an annual rate greater than 100% of the average value of the Portfolio’s portfolio) involves correspondingly greater expenses to the Portfolio, including brokerage commissions or dealer markups and other transaction costs on the sale of securities and reinvestments in other securities. Such sales may also result in realization of taxable capital gains, including short-term capital gains (which are generally taxed at ordinary income tax rates). The trading costs and tax effects associated with portfolio turnover may adversely affect the Portfolio’s performance. Please see the Portfolio's “Portfolio Summary—Portfolio Turnover” or the “Financial Highlights” in this prospectus for the portfolio turnover rates of the Portfolio.
Temporary Defensive Positions
For temporary defensive purposes, the Portfolio may invest without limit in U.S. debt securities, including taxable securities and short-term money market securities in attempting to respond to adverse market, economic, political, or other conditions, as determined by PIMCO. When the Portfolio engages in such strategies, it may not achieve its investment objective.
From time to time, as the prevailing market and interest rate environments warrant, and at the discretion of its portfolio manager, some portion of the Portfolio’s total net assets may be uninvested. In such cases, Portfolio assets will be held in cash in the Portfolio’s custody account. Cash assets are generally not income-generating and would impact the Portfolio’s performance.
Changes in Investment Objectives and Policies
The investment objective of the Portfolio is fundamental and may not be changed by the Board of Trustees without shareholder approval. Unless otherwise stated, all other investment policies of the Portfolio may be changed by the Board of Trustees without shareholder approval.
Percentage Investment Limitations
Unless otherwise stated, all percentage limitations on Portfolio investments listed in this prospectus will apply at the time of investment. The Portfolio would not violate these limitations unless an excess or deficiency occurs or exists immediately after and as a result of an investment.
Credit Ratings and Unrated Securities
Rating agencies are private services that provide ratings of the credit quality of fixed income securities, including convertible securities. Appendix A to this prospectus describes the various ratings assigned to fixed income securities by Moody’s, S&P and Fitch. Ratings assigned by a rating agency are not absolute standards of credit quality and do not

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evaluate market risks. Rating agencies may fail to make timely changes in credit ratings and an issuer’s current financial condition may be better or worse than a rating indicates. The Portfolio will not necessarily sell a security when its rating is reduced below its rating at the time of purchase. The ratings of a fixed income security may change over time. Moody’s, S&P and Fitch monitor and evaluate the ratings assigned to securities on an ongoing basis. As a result, debt instruments held by the Portfolio could receive a higher rating or a lower rating during the period in which they are held by the Portfolio. PIMCO does not rely solely on credit ratings, and develops its own analysis of issuer credit quality.
The Portfolio may purchase unrated securities (which are not rated by a rating agency) if PIMCO determines, in its sole discretion, that the security is of comparable quality to a rated security that the Portfolio may purchase. In making ratings determinations, PIMCO may take into account different factors than those taken into account by rating agencies, and PIMCO’s rating of a security may differ from the rating that a rating agency may have given the same security. Unrated securities may be less liquid than comparable rated securities and involve the risk that the portfolio manager may not accurately evaluate the security’s comparative credit rating. Analysis of the creditworthiness of issuers of high yield securities may be more complex than for issuers of higher-quality fixed income securities. To the extent that the Portfolio invests in high yield and/or unrated securities, the Portfolio’s success in achieving its investment objective may depend more heavily on the portfolio manager's creditworthiness analysis than if the Portfolio invested exclusively in higher-quality and rated securities.
Other Investments and Techniques
The Portfolio may invest in other types of securities and use a variety of investment techniques and strategies that are not described in this prospectus. These securities and techniques may subject the Portfolio to additional risks. Please see the SAI for additional information about the securities and investment techniques described in this prospectus and about additional securities and techniques that may be used by the Portfolio.
Cyber Security
As the use of technology has become more prevalent in the course of business, the Portfolio has become potentially more susceptible to operational and information security risks resulting from breaches in cyber security. A breach in cyber security refers to both intentional and unintentional cyber events that may, among other things, cause the Portfolio to lose proprietary information, suffer data corruption and/or destruction or lose operational capacity, result in the unauthorized release or other misuse of confidential information, or otherwise disrupt normal business operations. Cyber security breaches may involve unauthorized access to the Portfolio’s digital information systems (e.g., through “hacking” or malicious software coding), but may also result from outside attacks such as denial-of-service attacks (i.e., efforts to make network services unavailable to intended users). In addition, cyber security breaches involving the Portfolio’s third party service providers (including but not limited to advisers, administrators, transfer agents,
custodians, distributors and other third parties), trading counterparties or issuers in which the Portfolio invests can also subject the Portfolio to many of the same risks associated with direct cyber security breaches. Moreover, cyber security breaches involving trading counterparties or issuers in which the Portfolio invests could adversely impact such counterparties or issuers and cause the Portfolio’s investments to lose value.
Cyber security failures or breaches may result in financial losses to the Portfolio and its shareholders. These failures or breaches may also result in disruptions to business operations, potentially resulting in financial losses; interference with the Portfolio’s ability to calculate its NAV, process shareholder transactions or otherwise transact business with shareholders; impediments to trading; violations of applicable privacy and other laws; regulatory fines; penalties; reputational damage; reimbursement or other compensation costs; additional compliance and cyber security risk management costs and other adverse consequences. In addition, substantial costs may be incurred in order to prevent any cyber incidents in the future.
Like with operational risk in general, the Portfolio has established business continuity plans and risk management systems designed to reduce the risks associated with cyber security. However, there are inherent limitations in these plans and systems, including that certain risks may not have been identified, in large part because different or unknown threats may emerge in the future. As such, there is no guarantee that such efforts will succeed, especially because the Portfolios does not directly control the cyber security systems of issuers in which the Portfolio may invest, trading counterparties or third party service providers to the Portfolio. There is also a risk that cyber security breaches may not be detected. The Portfolio and its shareholders could be negatively impacted as a result.

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PIMCO Variable Insurance Trust

Financial Highlights
The financial highlights table is intended to help a shareholder understand the Portfolio’s financial performance for the last five fiscal years or, if shorter, the period since the Portfolio or class commenced operations. Certain information reflects financial results for a single Portfolio share. The total returns in the table represent the rate that an investor would have earned or lost on an investment in the Institutional Class shares of the Portfolio (assuming reinvestment of all dividends and distributions). The performance information does not reflect Variable Contract fees or expenses. This information has been audited by PricewaterhouseCoopers LLP, the Portfolio’s independent registered public accounting firm. Their report, along with full financial statements, appears in the Trust’s Annual Report, which is available upon request.
 
 
Investment Operations
Less Distributions(c)
 
 
 
 
Selected Per Share Data for
the Year or Period Ended^:
Net Asset Value
Beginning of
Year or Period(a)
Net Investment
Income (Loss)(b)
Net Realized/
Unrealized
Gain (Loss)
Total
From Net
Investment
Income
From Net
Realized
Capital Gain
Tax Basis
Return of
Capital
Total
PIMCO Total Return Portfolio
 
 
 
 
Institutional Class
 
 
 
 
 
 
 
 
12/31/2020
$11.02
$0.25
$0.71
$0.96
$(0.26)
$(0.13)
$0.00
$(0.39)
12/31/2019
10.48
0.34
0.54
0.88
(0.34)
0.00
0.00
(0.34)
12/31/2018
10.94
0.30
(0.34)
(0.04)
(0.29)
(0.13)
0.00
(0.42)
12/31/2017
10.64
0.26
0.28
0.54
(0.24)
0.00
0.00
(0.24)
12/31/2016
10.58
0.29
0.01
0.30
(0.24)
0.00
0.00
(0.24)
^
A zero balance may reflect actual amounts rounding to less than $0.01 or 0.01%.
(a)
Includes adjustments required by U.S. GAAP and may differ from net asset values and performance reported elsewhere by the Portfolio.
(b)
Per share amounts based on average number of shares outstanding during the year or period.
(c)
The tax characterization of distributions is determined in accordance with Federal income tax regulations. See Note 2, Distributions to Shareholders, in the Notes to Financial Statements for more information.

35  Prospectus | PIMCO Variable Insurance Trust


Prospectus
 
 
Ratios/Supplemental Data
 
 
 
Ratios to Average Net Assets
 
Net Asset Value End
of Year or Period(a)
Total
Return(a)
Net Assets End of
Year or Period
(000s)
Expenses
Expenses
Excluding Waivers
Expenses Excluding
Interest Expense
Expenses Excluding
Interest Expense
and Waivers
Net Investment
Income (Loss)
Portfolio
Turnover Rate
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
$11.59
8.81%
$160,779
0.54%
0.54%
0.50%
0.50%
2.22%
514%
11.02
8.52
129,771
0.71
0.71
0.50
0.50
3.11
534
10.48
(0.38)
83,675
0.76
0.76
0.50
0.50
2.78
631
10.94
5.07
83,041
0.54
0.54
0.50
0.50
2.43
574
10.64
2.83
92,502
0.51
0.51
0.50
0.50
2.71
512

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PIMCO Variable Insurance Trust

Appendix A
Description of Securities Ratings
The Portfolio’s investments may range in quality from securities rated in the lowest category in which the Portfolio is permitted to invest to securities rated in the highest category (as rated by Moody’s, Standard & Poor’s or Fitch, or, if unrated, determined by PIMCO to be of comparable quality). The percentage of the Portfolio’s assets invested in securities in a particular rating category will vary. The following terms are generally used to describe the credit quality of fixed income securities:
High Quality Debt Securitiesare those rated in one of the two highest rating categories (the highest category for commercial paper) or, if unrated, deemed comparable by PIMCO.
Investment Grade Debt Securitiesare those rated in one of the four highest rating categories, or if unrated deemed comparable by PIMCO.
Below Investment Grade High Yield Securities (“Junk Bonds”),are those rated lower than Baa by Moody’s, BBB by Standard & Poor’s or Fitch, and comparable securities. They are deemed predominantly speculative with respect to the issuer’s ability to repay principal and interest.
The following is a description of Moody’s, Standard & Poor’s and Fitch’s rating categories applicable to fixed income securities.
Moody’s Investors Service, Inc.
Global Long-Term Rating Scale
Ratings assigned on Moody’s global long-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Long-term ratings are assigned to issuers or obligations with an original maturity of one year or more and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Aaa: Obligations rated Aaa are judged to be of the highest quality, subject to the lowest level of credit risk.
Aa: Obligations rated Aa are judged to be of high quality and are subject to very low credit risk.
A: Obligations rated A are judged to be upper-medium grade and are subject to low credit risk.
Baa: Obligations rated Baa are judged to be medium-grade and subject to moderate credit risk and as such may possess certain speculative characteristics.
Ba: Obligations rated Ba are judged to be speculative and are subject to substantial credit risk.
B: Obligations rated B are considered speculative and are subject to high credit risk.
Caa: Obligations rated Caa are judged to be speculative of poor standing and are subject to very high credit risk.
Ca: Obligations rated Ca are highly speculative and are likely in, or very near, default, with some prospect of recovery of principal and interest.
C: Obligations rated C are the lowest rated and are typically in default, with little prospect for recovery of principal or interest.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category. Additionally, a “(hyb)” indicator is appended to all ratings of hybrid securities issued by banks, insurers, finance companies, and securities firms.*
* By their terms, hybrid securities allow for the omission of scheduled dividends, interest, or principal payments, which can potentially result in impairment if such an omission occurs. Hybrid securities may also be subject to contractually allowable write-downs of principal that could result in impairment. Together with the hybrid indicator, the long-term obligation rating assigned to a hybrid security is an expression of the relative credit risk associated with that security.
Medium-Term Note Program Ratings
Moody’s assigns provisional ratings to medium-term note (MTN) programs and definitive ratings to the individual debt securities issued from them (referred to as drawdowns or notes).
MTN program ratings are intended to reflect the ratings likely to be assigned to drawdowns issued from the program with the specified priority of claim (e.g., senior or subordinated). To capture the contingent nature of a program rating, Moody’s assigns provisional ratings to MTN programs. A provisional rating is denoted by a (P) in front of the rating.
The rating assigned to a drawdown from a rated MTN or bank/deposit note program is definitive in nature, and may differ from the program rating if the drawdown is exposed to additional credit risks besides the issuer’s default, such as links to the defaults of other issuers, or has other structural features that warrant a different rating. In some circumstances, no rating may be assigned to a drawdown.
Moody’s encourages market participants to contact Moody’s Ratings Desks or visit www.moodys.com directly if they have questions regarding ratings for specific notes issued under a medium-term note program. Unrated notes issued under an MTN program may be assigned an NR (not rated) symbol.
Global Short-Term Rating Scale
Ratings assigned on Moody’s global short-term rating scales are forward-looking opinions of the relative credit risks of financial obligations issued by non-financial corporates, financial institutions, structured finance vehicles, project finance vehicles, and public sector entities. Short-term ratings are assigned to obligations with an original maturity of thirteen months or less and reflect both on the likelihood of a default or impairment on contractual financial obligations and the expected financial loss suffered in the event of default or impairment.
Moody’s employs the following designations to indicate the relative repayment ability of rated issuers:

A-1  Prospectus | PIMCO Variable Insurance Trust

Prospectus

P-1: Ratings of Prime-1 reflect a superior ability to repay short-term debt obligations.
P-2: Ratings of Prime-2 reflect a strong ability to repay short-term debt obligations.
P-3: Ratings of Prime-3 reflect an acceptable ability to repay short-term obligations.
NP: Issuers (or supporting institutions) rated Not Prime do not fall within any of the Prime rating categories.
National Scale Long-Term Ratings
Moody’s long-term National Scale Ratings (NSRs) are opinions of the relative creditworthiness of issuers and financial obligations within a particular country. NSRs are not designed to be compared among countries; rather, they address relative credit risk within a given country. Moody’s assigns national scale ratings in certain local capital markets in which investors have found the global rating scale provides inadequate differentiation among credits or is inconsistent with a rating scale already in common use in the country.
In each specific country, the last two characters of the rating indicate the country in which the issuer is located or the financial obligation was issued (e.g., Aaa.ke for Kenya).
Aaa.n: Issuers or issues rated Aaa.n demonstrate the strongest creditworthiness relative to other domestic issuers and issuances.
Aa.n: Issuers or issues rated Aa.n demonstrate very strong creditworthiness relative to other domestic issuers and issuances.
A.n: Issuers or issues rated A.n present above-average creditworthiness relative to other domestic issuers and issuances.
Baa.n: Issuers or issues rated Baa.n represent average creditworthiness relative to other domestic issuers and issuances.
Ba.n: Issuers or issues rated Ba.n demonstrate below-average creditworthiness relative to other domestic issuers and issuances.
B.n: Issuers or issues rated B.n demonstrate weak creditworthiness relative to other domestic issuers and issuances.
Caa.n: Issuers or issues rated Caa.n demonstrate very weak creditworthiness relative to other domestic issuers and issuances.
Ca.n: Issuers or issues rated Ca.n demonstrate extremely weak creditworthiness relative to other domestic issuers and issuances.
C.n: Issuers or issues rated C.n demonstrate the weakest creditworthiness relative to other domestic issuers and issuances.
Moody’s appends numerical modifiers 1, 2, and 3 to each generic rating classification from Aa through Caa. The modifier 1 indicates that the obligation ranks in the higher end of its generic rating category; the modifier 2 indicates a mid-range ranking; and the modifier 3 indicates a ranking in the lower end of that generic rating category.
National Scale Short-Term Ratings
Moody’s short-term NSRs are opinions of the ability of issuers or issuances in a given country, relative to other domestic issuers or issuances, to repay debt obligations that have an original maturity not
exceeding thirteen months. Short-term NSRs in one country should not be compared with short-term NSRs in another country, or with Moody’s global ratings. There are four categories of short-term national scale ratings, generically denoted N-1 through N-4 as defined below.
In each specific country, the first two letters indicate the country in which the issuer is located (e.g., KE-1 through KE-4 for Kenya).
N-1: N-1 issuers or issuances represent the strongest likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-2: N-2 issuers or issuances represent an above average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-3: N-3 issuers or issuances represent an average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
N-4: N-4 issuers or issuances represent a below average likelihood of repayment of short-term senior unsecured debt obligations relative to other domestic issuers.
The short-term rating symbols P-1.za, P-2.za, P-3.za and NP.za are used in South Africa.
Short-Term Obligation Ratings
The Municipal Investment Grade (MIG) scale is used for US municipal cash flow notes, bond anticipation notes and certain other short-term obligations, which typically mature in three years or less. Under certain circumstances, the MIG scale is used for bond anticipation notes with maturities of up to five years.
MIG 1: This designation denotes superior credit quality. Excellent protection is afforded by established cash flows, highly reliable liquidity support, or demonstrated broad-based access to the market for refinancing.
MIG 2: This designation denotes strong credit quality. Margins of protection are ample, although not as large as in the preceding group.
MIG 3: This designation denotes acceptable credit quality. Liquidity and cash-flow protection may be narrow, and market access for refinancing is likely to be less well-established.
SG: This designation denotes speculative-grade credit quality. Debt instruments in this category may lack sufficient margins of protection.
Demand Obligation Ratings
In the case of variable rate demand obligations (VRDOs), a two-component rating is assigned. The components are a long-term rating and a short-term demand obligation rating. The long-term rating addresses the issuer’s ability to meet scheduled principal and interest payments. The short-term demand obligation rating addresses the ability of the issuer or the liquidity provider to make payments associated with the purchase-price-upon-demand feature (“demand feature”) of the VRDO. The short-term demand obligation rating uses the Variable Municipal Investment Grade (VMIG) scale.

April 30, 2021 | PROSPECTUS  A-2

PIMCO Variable Insurance Trust

VMIG 1: This designation denotes superior credit quality. Excellent protection is afforded by the superior short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 2: This designation denotes strong credit quality. Good protection is afforded by the strong short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
VMIG 3: This designation denotes acceptable credit quality. Adequate protection is afforded by the satisfactory short-term credit strength of the liquidity provider and structural and legal protections that ensure the timely payment of purchase price upon demand.
SG: This designation denotes speculative-grade credit quality. Demand features rated in this category may be supported by a liquidity provider that does not have a sufficiently strong short-term rating or may lack the structural or legal protections necessary to ensure the timely payment of purchase price upon demand.
Standard & Poor’s Ratings Services
Long-Term Issue Credit Ratings
Issue credit ratings are based, in varying degrees, on S&P Global Ratings’ (“S&P”) analysis of the following considerations:
Likelihood of payment—capacity and willingness of the obligor to meet its financial commitments on an obligation in accordance with the terms of the obligation;
Nature and provisions of the financial obligation and the promise S&P imputes; and
Protection afforded by, and relative position of, the financial obligation in the event of a bankruptcy, reorganization, or other arrangement under the laws of bankruptcy and other laws affecting creditors’ rights.
Issue ratings are an assessment of default risk, but may incorporate an assessment of relative seniority or ultimate recovery in the event of default. Junior obligations are typically rated lower than senior obligations, to reflect lower priority in bankruptcy, as noted above. (Such differentiation may apply when an entity has both senior and subordinated obligations, secured and unsecured obligations, or operating company and holding company obligations.)
Investment Grade
AAA: An obligation rated ‘AAA’ has the highest rating assigned by S&P. The obligor’s capacity to meet its financial commitments on the obligation is extremely strong.
AA: An obligation rated ‘AA’ differs from the highest-rated obligations only to a small degree. The obligor’s capacity to meet its financial commitments on the obligation is very strong.
A: An obligation rated ‘A’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher-rated categories. However, the obligor’s capacity to meet its financial commitments on the obligation is still strong.
BBB: An obligation rated ‘BBB’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken the obligor’s capacity to meet its financial commitments on the obligation.
Speculative Grade
Obligations rated ‘BB’, ‘B’, ‘CCC’, ‘CC’, and ‘C’ are regarded as having significant speculative characteristics. ‘BB’ indicates the least degree of speculation and ‘C’ the highest. While such obligations will likely have some quality and protective characteristics, these may be outweighed by large uncertainties or major exposure to adverse conditions.
BB: An obligation rated ‘BB’ is less vulnerable to nonpayment than other speculative issues. However, it faces major ongoing uncertainties or exposure to adverse business, financial, or economic conditions that could lead to the obligor’s inadequate capacity to meet its financial commitments on the obligation.
B: An obligation rated ‘B’ is more vulnerable to nonpayment than obligations rated ‘BB’, but the obligor currently has the capacity to meet its financial commitments on the obligation. Adverse business, financial, or economic conditions will likely impair the obligor’s capacity or willingness to meet its financial commitments on the obligation.
CCC: An obligation rated ‘CCC’ is currently vulnerable to nonpayment, and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation. In the event of adverse business, financial, or economic conditions, the obligor is not likely to have the capacity to meet its financial commitments on the obligation.
CC: An obligation rated ‘CC’ is currently highly vulnerable to nonpayment. The ‘CC’ rating is used when a default has not yet occurred, but S&P expects default to be a virtual certainty, regardless of the anticipated time to default.
C: An obligation rated ‘C’ is currently highly vulnerable to nonpayment, and the obligation is expected to have lower relative seniority or lower ultimate recovery compared with obligations that are rated higher.
D: An obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within five business days in the absence of a stated grace period or within the earlier of the stated grace period or 30 calendar days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
NR: This indicates that a rating has not been assigned or is no longer assigned.
Plus (+) or minus (-): The ratings from ‘AA’ to ‘CCC’ may be modified by the addition of a plus (+) or minus (-) sign to show relative standing within the rating categories.

A-3  Prospectus | PIMCO Variable Insurance Trust

Prospectus

Short-Term Issue Credit Ratings
A-1: A short-term obligation rated ‘A-1’ is rated in the highest category by S&P. The obligor’s capacity to meet its financial commitments on the obligation is strong. Within this category, certain obligations are designated with a plus sign (+). This indicates that the obligor’s capacity to meet its financial commitments on these obligations is extremely strong.
A-2: A short-term obligation rated ‘A-2’ is somewhat more susceptible to the adverse effects of changes in circumstances and economic conditions than obligations in higher rating categories. However, the obligor’s capacity to meet its financial commitments on the obligation is satisfactory.
A-3: A short-term obligation rated ‘A-3’ exhibits adequate protection parameters. However, adverse economic conditions or changing circumstances are more likely to weaken an obligor’s capacity to meet its financial commitments on the obligation.
B: A short-term obligation rated ‘B’ is regarded as vulnerable and has significant speculative characteristics. The obligor currently has the capacity to meet its financial commitments; however, it faces major ongoing uncertainties that could lead to the obligor’s inadequate capacity to meet its financial commitments.
C: A short-term obligation rated ‘C’ is currently vulnerable to nonpayment and is dependent upon favorable business, financial, and economic conditions for the obligor to meet its financial commitments on the obligation.
D: A short-term obligation rated ‘D’ is in default or in breach of an imputed promise. For non-hybrid capital instruments, the ‘D’ rating category is used when payments on an obligation are not made on the date due, unless S&P believes that such payments will be made within any stated grace period. However, any stated grace period longer than five business days will be treated as five business days. The ‘D’ rating also will be used upon the filing of a bankruptcy petition or the taking of a similar action and where default on an obligation is a virtual certainty, for example due to automatic stay provisions. A rating on an obligation is lowered to ‘D’ if it is subject to a distressed debt restructuring.
Dual Ratings: Dual ratings may be assigned to debt issues that have a put option or demand feature. The first component of the rating addresses the likelihood of repayment of principal and interest as due, and the second component of the rating addresses only the demand feature. The first component of the rating can relate to either a short-term or long-term transaction and accordingly use either short-term or long-term rating symbols. The second component of the rating relates to the put option and is assigned a short-term rating symbol (for example, ‘AAA/A-1+‘ or ‘A-1+/ A-1’). With U.S. municipal short-term demand debt, the U.S. municipal short-term note rating symbols are used for the first component of the rating (for example, ‘SP-1+/A-1+‘).
Active Qualifiers
S&P uses the following qualifiers that limit the scope of a rating. The structure of the transaction can require the use of a qualifier such as a ‘p’ qualifier, which indicates the rating addresses the principal portion of the obligation only. A qualifier appears as a suffix and is part of the rating.
L: Ratings qualified with ‘L’ apply only to amounts invested up to federal deposit insurance limits.
p: This suffix is used for issues in which the credit factors, the terms, or both, that determine the likelihood of receipt of payment of principal are different from the credit factors, terms or both that determine the likelihood of receipt of interest on the obligation. The ‘p’ suffix indicates that the rating addresses the principal portion of the obligation only and that the interest is not rated.
prelim: Preliminary ratings, with the ‘prelim’ suffix, may be assigned to obligors or obligations, including financial programs, in the circumstances described below. Assignment of a final rating is conditional on the receipt by S&P of appropriate documentation. S&P reserves the right not to issue a final rating. Moreover, if a final rating is issued, it may differ from the preliminary rating.
Preliminary ratings may be assigned to obligations, most commonly structured and project finance issues, pending receipt of final documentation and legal opinions.
Preliminary ratings may be assigned to obligations that will likely be issued upon the obligor’s emergence from bankruptcy or similar reorganization, based on late-stage reorganization plans, documentation and discussions with the obligor. Preliminary ratings may also be assigned to the obligors. These ratings consider the anticipated general credit quality of the reorganized or post-bankruptcy issuer as well as attributes of the anticipated obligation(s).
Preliminary ratings may be assigned to entities that are being formed or that are in the process of being independently established when, in S&P’s opinion, documentation is close to final. Preliminary ratings may also be assigned to the obligations of these entities.
Preliminary ratings may be assigned when a previously unrated entity is undergoing a well-formulated restructuring, recapitalization, significant financing or other transformative event, generally at the point that investor or lender commitments are invited. The preliminary rating may be assigned to the entity and to its proposed obligation(s). These preliminary ratings consider the anticipated general credit quality of the obligor, as well as attributes of the anticipated obligation(s), assuming successful completion of the transformative event. Should the transformative event not occur, S&P would likely withdraw these preliminary ratings.
A preliminary recovery rating may be assigned to an obligation that has a preliminary issue credit rating.

April 30, 2021 | PROSPECTUS  A-4

PIMCO Variable Insurance Trust

t: This symbol indicates termination structures that are designed to honor their contracts to full maturity or, should certain events occur, to terminate and cash settle all their contracts before their final maturity date.
cir: This symbol indicates a Counterparty Instrument Rating (CIR), which is a forward-looking opinion about the creditworthiness of an issuer in a securitization structure with respect to a specific financial obligation to a counterparty (including interest rate swaps, currency swaps, and liquidity facilities). The CIR is determined on an ultimate payment basis; these opinions do not take into account timeliness of payment.
Inactive Qualifiers (no longer applied or outstanding)
*:This symbol indicated that the rating was contingent upon S&P receipt of an executed copy of the escrow agreement or closing documentation confirming investments and cash flows. Discontinued use in August 1998.
c: This qualifier was used to provide additional information to investors that the bank may terminate its obligation to purchase tendered bonds if the long-term credit rating of the issuer was lowered to below an investment-grade level and/or the issuer’s bonds were deemed taxable. Discontinued use in January 2001.
G: The letter ‘G’ followed the rating symbol when a fund’s portfolio consisted primarily of direct U.S. government securities.
pi: This qualifier was used to indicate ratings that were based on an analysis of an issuer’s published financial information, as well as additional information in the public domain. Such ratings did not, however, reflect in-depth meetings with an issuer’s management and therefore, could have been based on less comprehensive information than ratings without a ‘pi’ suffix. Discontinued use as of December 2014 and as of August 2015 for Lloyd’s Syndicate Assessments.
pr: The letters ‘pr’ indicate that the rating was provisional. A provisional rating assumed the successful completion of a project financed by the debt being rated and indicates that payment of debt service requirements was largely or entirely dependent upon the successful, timely completion of the project. This rating, however, while addressing credit quality subsequent to completion of the project, made no comment on the likelihood of or the risk of default upon failure of such completion.
q: A ‘q’ subscript indicates that the rating is based solely on quantitative analysis of publicly available information. Discontinued use in April 2001.
r: The ‘r’ modifier was assigned to securities containing extraordinary risks, particularly market risks, that are not covered in the credit rating. The absence of an ‘r’ modifier should not be taken as an indication that an obligation would not exhibit extraordinary non-credit related risks. S&P discontinued the use of the ‘r’ modifier for most obligations in June 2000 and for the balance of obligations (mainly structured finance transactions) in November 2002.
Fitch Ratings
Long-Term Credit Ratings
Investment Grade
Rated entities in a number of sectors, including financial and non-financial corporations, sovereigns, insurance companies and certain sectors within public finance, are generally assigned Issuer Default Ratings (“IDRs”). IDRs are also assigned to certain entities or enterprises in global infrastructure, project finance, and public finance. IDRs opine on an entity’s relative vulnerability to default (including by way of a distressed debt exchange) on financial obligations. The threshold default risk addressed by the IDR is generally that of the financial obligations whose non-payment would best reflect the uncured failure of that entity. As such, IDRs also address relative vulnerability to bankruptcy, administrative receivership or similar concepts.
In aggregate, IDRs provide an ordinal ranking of issuers based on the agency’s view of their relative vulnerability to default, rather than a prediction of a specific percentage likelihood of default.
AAA: Highest credit quality. ‘AAA’ ratings denote the lowest expectation of default risk. They are assigned only in cases of exceptionally strong capacity for payment of financial commitments. This capacity is highly unlikely to be adversely affected by foreseeable events.
AA: Very high credit quality. ‘AA’ ratings denote expectations of very low default risk. They indicate very strong capacity for payment of financial commitments. This capacity is not significantly vulnerable to foreseeable events.
A: High credit quality. ‘A’ ratings denote expectations of low default risk. The capacity for payment of financial commitments is considered strong. This capacity may, nevertheless, be more vulnerable to adverse business or economic conditions than is the case for higher ratings.
BBB: Good credit quality. ‘BBB’ ratings indicate that expectations of default risk are currently low. The capacity for payment of financial commitments is considered adequate, but adverse business or economic conditions are more likely to impair this capacity.
Speculative Grade
BB: Speculative. ‘BB’ ratings indicate an elevated vulnerability to default risk, particularly in the event of adverse changes in business or economic conditions over time; however, business or financial flexibility exists that supports the servicing of financial commitments.
B: Highly speculative. ‘B’ ratings indicate that material default risk is present, but a limited margin of safety remains. Financial commitments are currently being met, however, capacity for continued payment is vulnerable to deterioration in the business and economic environment.
CCC: Substantial credit risk. Default is a real possibility.
CC: Very high levels of credit risk. Default of some kind appears probable.
C: Near default.

A-5  Prospectus | PIMCO Variable Insurance Trust

Prospectus

A default or default-like process has begun, or the issuer is in standstill, or for a closed funding vehicle, payment capacity is irrevocably impaired. Conditions that are indicative of a ‘C’ category rating for an issuer include:
a. the issuer has entered into a grace or cure period following non-payment of a material financial obligation;
b. the issuer has entered into a temporary negotiated waiver or standstill agreement following a payment default on a material financial obligation;
c. the formal announcement by the issuer or their agent of a distressed debt exchange;
d. a closed financing vehicle where payment capacity is irrevocably impaired such that it is not expected to pay interest and/or principal in full during the life of the transaction, but where no payment default is imminent
RD: Restricted default. ‘RD’ ratings indicate an issuer that in Fitch Ratings’ opinion has experienced an uncured payment default or distressed debt exchange on a bond, loan or other material financial obligation but which has not entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure, and which has not otherwise ceased operating. This would include:
i. the selective payment default on a specific class or currency of debt;
ii. the uncured expiry of any applicable grace period, cure period or default forbearance period following a payment default on a bank loan, capital markets security or other material financial obligation;
iii. the extension of multiple waivers or forbearance periods upon a payment default on one or more material financial obligations, either in series or in parallel; ordinary execution of a distressed debt exchange on one or more material financial obligations.
D: Default. ‘D’ ratings indicate an issuer that in Fitch Ratings’ opinion has entered into bankruptcy filings, administration, receivership, liquidation or other formal winding-up procedure or that has otherwise ceased business. Default ratings are not assigned prospectively to entities or their obligations; within this context, non-payment on an instrument that contains a deferral feature or grace period will generally not be considered a default until after the expiration of the deferral or grace period, unless a default is otherwise driven by bankruptcy or other similar circumstance, or by a distressed debt exchange.
In all cases, the assignment of a default rating reflects the agency’s opinion as to the most appropriate rating category consistent with the rest of its universe of ratings, and may differ from the definition of default under the terms of an issuer’s financial obligations or local commercial practice.
The modifiers “+” or “-” may be appended to a rating to denote relative status within major rating categories. For example, the rating category ‘AA’ has three notch-specific rating levels (’AA+‘; ’AA’; ‘AA-’; each a rating level). Such suffixes are not added to ‘AAA’ ratings and ratings below the ‘CCC’ category.
Recovery Ratings
Recovery Ratings are assigned to selected individual securities and obligations, most frequently for individual obligations of corporate finance issuers with IDRs in speculative grade categories.
Among the factors that affect recovery rates for securities are the collateral, the seniority relative to other obligations in the capital structure (where appropriate), and the expected value of the company or underlying collateral in distress.
The Recovery Rating scale is based on the expected relative recovery characteristics of an obligation upon the curing of a default, emergence from insolvency or following the liquidation or termination of the obligor or its associated collateral.
Recovery Ratings are an ordinal scale and do not attempt to precisely predict a given level of recovery. As a guideline in developing the rating assessments, the agency employs broad theoretical recovery bands in its ratings approach based on historical averages and analytical judgment, but actual recoveries for a given security may deviate materially from historical averages.
RR1: Outstanding recovery prospects given default. ‘RR1’ rated securities have characteristics consistent with securities historically recovering 91%-100% of current principal and related interest.
RR2: Superior recovery prospects given default. ‘RR2’ rated securities have characteristics consistent with securities historically recovering 71%-90% of current principal and related interest.
RR3: Good recovery prospects given default. ‘RR3’ rated securities have characteristics consistent with securities historically recovering 51%-70% of current principal and related interest.
RR4: Average recovery prospects given default. ‘RR4’ rated securities have characteristics consistent with securities historically recovering 31%-50% of current principal and related interest.
RR5: Below average recovery prospects given default. ‘RR5’ rated securities have characteristics consistent with securities historically recovering 11%-30% of current principal and related interest.
RR6: Poor recovery prospects given default. ‘RR6’ rated securities have characteristics consistent with securities historically recovering 0%-10% of current principal and related interest.
Short-Term Credit Ratings
A short-term issuer or obligation rating is based in all cases on the short-term vulnerability to default of the rated entity and relates to the capacity to meet financial obligations in accordance with the documentation governing the relevant obligation. Short-term deposit ratings may be adjusted for loss severity. Short-Term Ratings are assigned to obligations whose initial maturity is viewed as “short term” based on market convention. Typically, this means up to 13 months for corporate, sovereign, and structured obligations, and up to 36 months for obligations in U.S. public finance markets.
F1: Highest short-term credit quality. Indicates the strongest intrinsic capacity for timely payment of financial commitments; may have an added “+” to denote any exceptionally strong credit feature.

April 30, 2021 | PROSPECTUS  A-6

PIMCO Variable Insurance Trust

F2: Good short-term credit quality. Good intrinsic capacity for timely payment of financial commitments.
F3: Fair short-term credit quality. The intrinsic capacity for timely payment of financial commitments is adequate.
B: Speculative short-term credit quality. Minimal capacity for timely payment of financial commitments, plus heightened vulnerability to near term adverse changes in financial and economic conditions.
C: High short-term default risk. Default is a real possibility.
RD: Restricted default. Indicates an entity that has defaulted on one or more of its financial commitments, although it continues to meet other financial obligations. Typically applicable to entity ratings only.
D: Default. Indicates a broad-based default event for an entity, or the default of a short-term obligation.

A-7  Prospectus | PIMCO Variable Insurance Trust

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INVESTMENT ADVISER AND ADMINISTRATOR
PIMCO, 650 Newport Center Drive, Newport Beach, CA 92660
DISTRIBUTOR
PIMCO Investments LLC, 1633 Broadway, New York, NY 10019
CUSTODIAN
State Street Bank & Trust Co., 801 Pennsylvania Avenue, Kansas City, MO 64105
TRANSFER AGENT
DST Asset Manager Solutions, Inc.,
430 W 7th Street STE 219024, Kansas City, MO 64105
INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM
PricewaterhouseCoopers LLP, 1100 Walnut Street, Suite 1300, Kansas City, MO 64106-2197
LEGAL COUNSEL
Dechert LLP, 1900 K Street N.W., Washington, D.C. 20006

PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
The Trust’s SAI and annual and semi-annual reports to shareholders include additional information about the Portfolio. The SAI is incorporated by reference into this Prospectus, which means it is part of this Prospectus for legal purposes. The Portfolio's annual report discusses the market conditions and investment strategies that significantly affected the Portfolio's performance during its last fiscal year.
The SAI contains detailed information about Portfolio purchase, redemption and exchange options and procedures and other information about the Portfolio. You can get a free copy of the SAI.
You may get free copies of any of these materials, or request other information about the Portfolio by calling the Trust at 1-800-927-4648, by visiting www.pimco.com/pvit or by writing to:
PIMCO Variable Insurance Trust
650 Newport Center Drive
Newport Beach, CA 92660
Daily updates on the NAV of the Portfolio may be obtained by calling 1-888-87-PIMCO.
You may access reports and other information about the Trust on the EDGAR Database on the Commission’s Web site at www.sec.gov. You may get copies of additional information about the Trust, including its SAI, with payment of a duplication fee, by e-mailing your request to publicinfo@sec.gov. You can also visit our web site at www.pimco.com/pvit for additional information about the Portfolio, including the SAI and the annual and semi-annual reports, which are available for download free of charge.
Reference the Trust’s Investment Company Act file number in your correspondence.
Investment Company Act File Number: 811-08399
PVIT0597F_043021